document_title: Steam turbine

question_text: who described the basic mechanism of steam reaction

question_tokens: who described the basic mechanism of steam reaction

text: Steam turbine

text: History[edit]

text: The first device that may be classified as a reaction steam turbine was little more than a toy, the classic Aeolipile, described in the 1st century by Hero of Alexandria in Roman Egypt.[4][5][6]  In 1551, Taqi al-Din in Ottoman Egypt described a steam turbine with the practical application of rotating a spit.  Steam turbines were also described by the Italian Giovanni Branca (1629)[7] and John Wilkins in England (1648).[8] The devices described by Taqi al-Din and Wilkins are today known as steam jacks. In 1672 an impulse steam turbine driven car was designed by Ferdinand Verbiest. A more modern version of this car was produced some time in the late 18th century by an unknown German mechanic. In 1775 at Soho James Watt designed a reaction turbine that was put to work there.[9] In 1827 the Frenchmen Real and Pichon patented and constructed a compound impulse turbine.[10]

text: The modern steam turbine was invented in 1884 by Sir Charles Parsons, whose first model was connected to a dynamo that generated 7.5 kW (10 hp) of electricity.[11] The invention of Parsons' steam turbine made cheap and plentiful electricity possible and revolutionized marine transport and naval warfare.[12] Parsons' design was a reaction type. His patent was licensed and the turbine scaled-up shortly after by an American, George Westinghouse. The Parsons turbine also turned out to be easy to scale up. Parsons had the satisfaction of seeing his invention adopted for all major world power stations, and the size of generators had increased from his first 7.5 kW set up to units of 50,000 kW capacity. Within Parson's lifetime, the generating capacity of a unit was scaled up by about 10,000 times,[13] and the total output from turbo-generators constructed by his firm C. A. Parsons and Company and by their licensees, for land purposes alone, had exceeded thirty million horse-power.[11]

text: A number of other variations of turbines have been developed that work effectively with steam. The de Laval turbine (invented by Gustaf de Laval) accelerated the steam to full speed before running it against a turbine blade.  De Laval's impulse turbine is simpler, less expensive and does not need to be pressure-proof. It can operate with any pressure of steam, but is considerably less efficient.[citation needed] Auguste Rateau developed a pressure compounded impulse turbine using the de Laval principle as early as 1896,[14] obtained a US patent in 1903, and applied the turbine to a French torpedo boat in 1904.  He taught at the École des mines de Saint-Étienne for a decade until 1897, and later founded a successful company that was incorporated into the Alstom firm after his death.  One of the founders of the modern theory of steam and gas turbines was Aurel Stodola, a Slovak physicist and engineer and professor at the Swiss Polytechnical Institute (now ETH) in Zurich. His work Die Dampfturbinen und ihre Aussichten als Wärmekraftmaschinen (English: The Steam Turbine and its prospective use as a Heat Engine) was published in Berlin in 1903. A further book Dampf und Gas-Turbinen (English: Steam and Gas Turbines) was published in 1922.

text: The Brown-Curtis turbine, an impulse type, which had been originally developed and patented by the U.S. company International Curtis Marine Turbine Company, was developed in the 1900s in conjunction with John Brown & Company. It was used in John Brown-engined merchant ships and warships, including liners and Royal Navy warships.

text: Manufacturing[edit]

text: The present-day manufacturing industry for steam turbines is dominated by Chinese power equipment makers. Harbin Electric, Shanghai Electric, and Dongfang Electric, the top three power equipment makers in China, collectively hold a majority stake in the worldwide market share for steam turbines in 2009-10 according to Platts.[15] Other manufacturers with minor market share include Bharat Heavy Electricals Limited, Siemens, Alstom, General Electric, Doosan Škoda Power, Mitsubishi Heavy Industries, and Toshiba.[15] The consulting firm Frost & Sullivan projects that manufacturing of steam turbines will become more consolidated by 2020 as Chinese power manufacturers win increasing business outside of China.[16]

text: Types[edit]

text: Steam turbines are made in a variety of sizes ranging from small <0.75 kW (<1 hp) units (rare) used as mechanical drives for pumps, compressors and other shaft driven equipment, to 1.5 GW (2,000,000 hp) turbines used to generate electricity. There are several classifications for modern steam turbines.

text: Blade and stage design[edit]

text: Turbine blades are of two basic types, blades and nozzles. Blades move entirely due to the impact of steam on them and their profiles do not converge. This results in a steam velocity drop and essentially no pressure drop as steam moves through the blades. A turbine composed of blades alternating with fixed nozzles is called an impulse turbine, Curtis turbine, Rateau turbine, or Brown-Curtis turbine. Nozzles appear similar to blades, but their profiles converge near the exit. This results in a steam pressure drop and velocity increase as steam moves through the nozzles. Nozzles move due to both the impact of steam on them and the reaction due to the high-velocity steam at the exit. A turbine composed of moving nozzles alternating with fixed nozzles is called a reaction turbine or Parsons turbine.

text: Except for low-power applications, turbine blades are arranged in multiple stages in series, called compounding, which greatly improves efficiency at low speeds.[17] A reaction stage is a row of fixed nozzles followed by a row of moving nozzles. Multiple reaction stages divide the pressure drop between the steam inlet and exhaust into numerous small drops, resulting in a pressure-compounded turbine. Impulse stages may be either pressure-compounded, velocity-compounded, or pressure-velocity compounded. A pressure-compounded impulse stage is a row of fixed nozzles followed by a row of moving blades, with multiple stages for compounding. This is also known as a Rateau turbine, after its inventor. A velocity-compounded impulse stage (invented by Curtis and also called a "Curtis wheel") is a row of fixed nozzles followed by two or more rows of moving blades alternating with rows of fixed blades. This divides the velocity drop across the stage into several smaller drops.[18] A series of velocity-compounded impulse stages is called a pressure-velocity compounded turbine.

text: By 1905, when steam turbines were coming into use on fast ships (such as HMS Dreadnought) and in land-based power applications, it had been determined that it was desirable to use one or more Curtis wheels at the beginning of a multi-stage turbine (where the steam pressure is highest), followed by reaction stages. This was more efficient with high-pressure steam due to reduced leakage between the turbine rotor and the casing.[19] This is illustrated in the drawing of the German 1905 AEG marine steam turbine. The steam from the boilers enters from the right at high pressure through a throttle, controlled manually by an operator (in this case a sailor known as the throttleman). It passes through five Curtis wheels and numerous reaction stages (the small blades at the edges of the two large rotors in the middle) before exiting at low pressure, almost certainly to a condenser. The condenser provides a vacuum that maximizes the energy extracted from the steam, and condenses the steam into feedwater to be returned to the boilers. On the left are several additional reaction stages (on two large rotors) that rotate the turbine in reverse for astern operation, with steam admitted by a separate throttle. Since ships are rarely operated in reverse, efficiency is not a priority in astern turbines, so only a few stages are used to save cost.

text: Blade design challenges[edit]

text: A major challenge facing turbine design was reducing the creep experienced by the blades. Because of the high temperatures and high stresses of operation, steam turbine materials become damaged through these mechanisms. As temperatures are increased in an effort to improve turbine efficiency, creep becomes  significant. To limit creep, thermal coatings and superalloys with solid-solution strengthening and grain boundary strengthening are used in blade designs.

text: Protective coatings are used to reduce the thermal damage and to limit oxidation. These coatings are often stabilized zirconium dioxide-based ceramics. Using a thermal protective coating limits the temperature exposure of the nickel superalloy. This reduces the creep mechanisms experienced in the blade. Oxidation coatings limit efficiency losses caused by a buildup on the outside of the blades, which is especially important in the high-temperature environment.[20]

text: The nickel-based blades are alloyed with aluminum and titanium to improve strength and creep resistance. The microstructure of these alloys is composed of different regions of composition. A uniform dispersion of the gamma-prime phase – a combination of nickel, aluminum, and titanium – promotes the strength and creep resistance of the blade due to the microstructure.[21]

text: Refractory elements such as rhenium and ruthenium can be added to the alloy to improve creep strength. The addition of these elements reduces the diffusion of the gamma prime phase, thus preserving the fatigue resistance, strength, and creep resistance.[22]

text: Steam supply and exhaust conditions[edit]

text: These types include condensing, non-condensing, reheat, extraction and induction.

text: Condensing turbines are most commonly found in electrical power plants. These turbines receive steam from a boiler and exhaust it to a condenser. The exhausted steam is at a pressure well below atmospheric, and is in a partially condensed state, typically of a quality near 90%.

text: Non-condensing or back pressure turbines are most widely used for process steam applications. The exhaust pressure is controlled by a regulating valve to suit the needs of the process steam pressure. These are commonly found at refineries, district heating units, pulp and paper plants, and desalination facilities where large amounts of low pressure process steam are needed.

text: Reheat turbines are also used almost exclusively in electrical power plants. In a reheat turbine, steam flow exits from a high-pressure section of the turbine and is returned to the boiler where additional superheat is added. The steam then goes back into an intermediate pressure section of the turbine and continues its expansion. Using reheat in a cycle increases the work output from the turbine and also the expansion reaches conclusion before the steam condenses, thereby minimizing the erosion of the blades in last rows. In most of the cases, maximum number of reheats employed in a cycle is 2 as the cost of super-heating the steam negates the increase in the work output from turbine.

text: Extracting type turbines are common in all applications. In an extracting type turbine, steam is released from various stages of the turbine, and used for industrial process needs or sent to boiler feedwater heaters to improve overall cycle efficiency.  Extraction flows may be controlled with a valve, or left uncontrolled. Extracted steam results in a loss of power in the downstream stages of the turbine.

text: Induction turbines introduce low pressure steam at an intermediate stage to produce additional power.

text: Casing or shaft arrangements[edit]

text: These arrangements include single casing, tandem compound and cross compound turbines. Single casing units are the most basic style where a single casing and shaft are coupled to a generator. Tandem compound are used where two or more casings are directly coupled together to drive a single generator. A cross compound turbine arrangement features two or more shafts not in line driving two or more generators that often operate at different speeds. A cross compound turbine is typically used for many large applications. A typical 1930s-1960s naval installation is illustrated below; this shows high- and low-pressure turbines driving a common reduction gear, with a geared cruising turbine on one high-pressure turbine.

text: Two-flow rotors[edit]

text: The moving steam imparts both a tangential and axial thrust on the turbine shaft, but the axial thrust in a simple turbine is unopposed. To maintain the correct rotor position and balancing, this force must be counteracted by an opposing force. Thrust bearings can be used for the shaft bearings, the rotor can use dummy pistons, it can be double flow- the steam enters in the middle of the shaft and exits at both ends, or a combination of any of these. In a double flow rotor, the blades in each half face opposite ways, so that the axial forces negate each other but the tangential forces act together. This design of rotor is also called two-flow, double-axial-flow, or double-exhaust. This arrangement is common in low-pressure casings of a compound turbine.[23]

text: Principle of operation and design[edit]

text: An ideal steam turbine is considered to be an isentropic process, or constant entropy process, in which the entropy of the steam entering the turbine is equal to the entropy of the steam leaving the turbine. No steam turbine is truly isentropic, however, with typical isentropic efficiencies ranging from 20–90% based on the application of the turbine. The interior of a turbine comprises several sets of blades or buckets. One set of stationary blades is connected to the casing and one set of rotating blades is connected to the shaft. The sets intermesh with certain minimum clearances, with the size and configuration of sets varying to efficiently exploit the expansion of steam at each stage.

text: Practical thermal efficiency of a steam turbine varies with turbine size, load condition, gap losses and friction losses. They reach top values up to about 50% in a 1200 MW turbine; smaller ones have a lower efficiency.[citation needed] To maximize turbine efficiency the steam is expanded, doing work, in a number of stages. These stages are characterized by how the energy is extracted from them and are known as either impulse or reaction turbines. Most steam turbines use a mixture of the reaction and impulse designs: each stage behaves as either one or the other, but the overall turbine uses both. Typically, lower pressure sections are reaction type and higher pressure stages are impulse type.[citation needed]

text: Impulse turbines[edit]

text:
An impulse turbine has fixed nozzles that orient the steam flow into high speed jets. These jets contain significant kinetic energy,  which is converted into shaft rotation by the bucket-like shaped rotor blades, as the steam jet changes direction. A pressure drop occurs across only the stationary blades, with a net increase in steam velocity across the stage.
As the steam flows through the nozzle its pressure falls from inlet pressure to the exit pressure (atmospheric pressure, or more usually, the condenser vacuum). Due to this high ratio of expansion of steam, the steam leaves the nozzle with a very high velocity. The steam leaving the moving blades has a large portion of the maximum velocity of the steam when leaving the nozzle. The loss of energy due to this higher exit velocity is commonly called the carry over velocity or leaving loss.

text: The law of moment of momentum states that the sum of the moments of external forces acting on a fluid which is temporarily occupying the control volume is equal to the net time change of angular momentum flux through the control volume.

text:
The swirling fluid enters the control volume at radius

r

1

{\displaystyle r_{1}}

 with tangential velocity

V

w
1

{\displaystyle V_{w1}}

 and leaves at radius

r

2

{\displaystyle r_{2}}

 with tangential velocity

V

w
2

{\displaystyle V_{w2}}

.

text: A velocity triangle paves the way for a better understanding of the relationship between the various velocities. In the adjacent figure we have:

text: Then by the law of moment of momentum, the torque on the fluid is given by:

text:
T
=

m
˙

(

r

2

V

w
2

−

r

1

V

w
1

)

{\displaystyle T={\dot {m}}(r_{2}V_{w2}-r_{1}V_{w1})}

text:
For an impulse steam turbine:

r

2

=

r

1

=
r

{\displaystyle r_{2}=r_{1}=r}

. Therefore, the tangential force on the blades is

F

u

=

m
˙

(

V

w
1

−

V

w
2

)

{\displaystyle F_{u}={\dot {m}}(V_{w1}-V_{w2})}

. The work done per unit time or power developed:

W

=

T
∗
ω

{\displaystyle {W}={T*\omega }}

.

text:
When ω is the angular velocity of the turbine, then the blade speed is

U

=

ω
∗
r

{\displaystyle {U}={\omega *r}}

. The power developed is then

W
=

m
˙

U
(

Δ

V

w

)

{\displaystyle W={\dot {m}}U({\Delta }V_{w})}

.

text: Blade efficiency

text:
Blade efficiency (

η

b

{\displaystyle {\eta _{b}}}

) can be defined as the ratio of the work done on the blades to kinetic energy supplied to the fluid, and is given by

text:
η

b

=

W
o
r
k

D
o
n
e

K
i
n
e
t
i
c

E
n
e
r
g
y

S
u
p
p
l
i
e
d

=

2
U

V

w

V

1

2

{\displaystyle {\eta _{b}}={\frac {Work~Done}{Kinetic~Energy~Supplied}}={\frac {2UV_{w}}{V_{1}^{2}}}}

text: Stage efficiency

text: A stage of an impulse turbine consists of a nozzle set and a moving wheel. The stage efficiency defines a relationship between enthalpy drop in the nozzle and work done in the stage.

text:
η

s
t
a
g
e

=

W
o
r
k

d
o
n
e

o
n

b
l
a
d
e

E
n
e
r
g
y

s
u
p
p
l
i
e
d

p
e
r

s
t
a
g
e

=

U
Δ

V

w

Δ
h

{\displaystyle {\eta _{stage}}={\frac {Work~done~on~blade}{Energy~supplied~per~stage}}={\frac {U\Delta V_{w}}{\Delta h}}}

text:
Where

Δ
h

=

h

2

−

h

1

{\displaystyle {\Delta h}=h_{2}-h_{1}}

  is the specific enthalpy drop of steam in the nozzle.

text:
By the first law of thermodynamics:

h

1

+

V

1

2

2

=

h

2

+

V

2

2

2

{\displaystyle {h_{1}}+{\frac {V_{1}^{2}}{2}}={h_{2}}+{\frac {V_{2}^{2}}{2}}}

text:
Assuming that

V

1

{\displaystyle V_{1}}

 is appreciably less than

V

2

{\displaystyle V_{2}}

, we get

Δ
h

{\displaystyle {\Delta h}}

 ≈

V

2

2

2

{\displaystyle {\frac {V_{2}^{2}}{2}}}

Furthermore, stage efficiency is the product of blade efficiency and nozzle efficiency, or

η

s
t
a
g
e

=

η

b

∗

η

N

{\displaystyle {\eta _{stage}}={\eta _{b}}*{\eta _{N}}}

text:
Nozzle efficiency is given by

η

N

{\displaystyle {\eta _{N}}}

 =

V

2

2

2
(

h

1

−

h

2

)

{\displaystyle {\frac {V_{2}^{2}}{2(h_{1}-h_{2})}}}

, where the enthalpy (in J/Kg) of steam at the entrance of the nozzle is

h

1

{\displaystyle h_{1}}

 and the enthalpy of steam at the exit of the nozzle is

h

2

{\displaystyle h_{2}}

.

Δ

V

w

=

V

w
1

−
(
−

V

w
2

)

{\displaystyle {\Delta V_{w}}=V_{w1}-(-V_{w2})}

Δ

V

w

=

V

w
1

+

V

w
2

{\displaystyle {\Delta V_{w}}=V_{w1}+V_{w2}}

Δ

V

w

=

V

r
1

cos

β

1

+

V

r
2

cos

β

2

{\displaystyle {\Delta V_{w}}={V_{r1}\cos \beta _{1}+V_{r2}\cos \beta _{2}}}

Δ

V

w

=

V

r
1

cos

β

1

(
1
+

V

r
2

cos

β

2

V

r
1

cos

β

1

)

{\displaystyle {\Delta V_{w}}={V_{r1}\cos \beta _{1}}(1+{\frac {V_{r2}\cos \beta _{2}}{V_{r1}\cos \beta _{1}}})}

text:
The ratio of the cosines of the blade angles at the outlet and inlet can be taken and denoted

c

=

cos

β

2

cos

β

1

{\displaystyle {c}={\frac {\cos \beta _{2}}{\cos \beta _{1}}}}

.
The ratio of steam velocities relative to the rotor speed at the outlet to the inlet of the blade is defined by the friction coefficient

k

=

V

r
2

V

r
1

{\displaystyle {k}={\frac {V_{r2}}{V_{r1}}}}

.

text:
k
<
1

{\displaystyle k<1}

 and depicts the loss in the relative velocity due to friction as the steam flows around the blades (

k
=
1

{\displaystyle k=1}

 for smooth blades).

text:
η

b

=

2
U
Δ

V

w

V

1

2

=

2
U
(
cos

α

1

−
U

/

V

1

)
(
1
+
k
c
)

V

1

{\displaystyle {\eta _{b}}={\frac {2U\Delta V_{w}}{V_{1}^{2}}}={\frac {2U(\cos \alpha _{1}-U/V_{1})(1+kc)}{V_{1}}}}

text:
The ratio of the blade speed to the absolute steam velocity at the inlet is termed the blade speed ratio

ρ

{\displaystyle {\rho }}

 =

U

V

1

{\displaystyle {\frac {U}{V_{1}}}}

text:
η

b

{\displaystyle {\eta _{b}}}

 is maximum when

d

η

b

d
ρ

=
0

{\displaystyle {d\eta _{b} \over d\rho }=0}

 or,

d

d
ρ

(
2

cos

α

1

−

ρ

2

(
1
+
k
c
)
)
=
0

{\displaystyle {\frac {d}{d\rho }}(2{\cos \alpha _{1}-\rho ^{2}}(1+kc))=0}

. That implies

ρ

=

cos

α

1

2

{\displaystyle {\rho }={\frac {\cos \alpha _{1}}{2}}}

 and therefore

U

V

1

=

cos

α

1

2

{\displaystyle {\frac {U}{V_{1}}}={\frac {\cos \alpha _{1}}{2}}}

. Now

ρ

o
p
t

=

U

V

1

=

cos

α

1

2

{\displaystyle {\rho _{opt}}={\frac {U}{V_{1}}}={\frac {\cos \alpha _{1}}{2}}}

 (for a single stage impulse turbine)

text:
Therefore, the maximum value of stage efficiency is obtained by putting the value of

U

V

1

=

cos

α

1

2

{\displaystyle {\frac {U}{V_{1}}}={\frac {\cos \alpha _{1}}{2}}}

 in the expression of

η

b

{\displaystyle {\eta _{b}}}

/

text:
We get:

(

η

b

)

m
a
x

=
2
(
ρ
cos

α

1

−

ρ

2

)
(
1
+
k
c
)
=

cos

2

α

1

(
1
+
k
c
)

2

{\displaystyle {(\eta _{b})_{max}}=2(\rho \cos \alpha _{1}-\rho ^{2})(1+kc)={\frac {\cos ^{2}\alpha _{1}(1+kc)}{2}}}

.

text:
For equiangular blades,

β

1

=

β

2

{\displaystyle \beta _{1}=\beta _{2}}

, therefore

c
=
1

{\displaystyle c=1}

, and we get

(

η

b

)

m
a
x

=

c
o

s

2

α

1

(
1
+
k
)

2

{\displaystyle {(\eta _{b})_{max}}={\frac {cos^{2}\alpha _{1}(1+k)}{2}}}

. If the friction due to the blade surface is neglected then

(

η

b

)

m
a
x

=

cos

2

α

1

{\displaystyle {(\eta _{b})_{max}}={\cos ^{2}\alpha _{1}}}

.

text: Conclusions on maximum efficiency

text:
(

η

b

)

m
a
x

=

cos

2

α

1

{\displaystyle {(\eta _{b})_{max}}={\cos ^{2}\alpha _{1}}}

text:
1. For a given steam velocity work done per kg of steam would be maximum when

cos

2

α

1

=
1

{\displaystyle {\cos ^{2}\alpha _{1}}=1}

 or

α

1

=
0

{\displaystyle \alpha _{1}=0}

.

text:
2. As

α

1

{\displaystyle \alpha _{1}}

 increases, the work done on the blades reduces, but at the same time surface area of the blade reduces, therefore there are less frictional losses.

text: Reaction turbines[edit]

text: In the reaction turbine, the rotor blades themselves are arranged to form convergent nozzles. This type of turbine makes use of the reaction force produced as the steam accelerates through the nozzles formed by the rotor. Steam is directed onto the rotor by the fixed vanes of the stator. It leaves the stator as a jet that fills the entire circumference of the rotor. The steam then changes direction and increases its speed relative to the speed of the blades. A pressure drop occurs across both the stator and the rotor, with steam accelerating through the stator and decelerating through the rotor, with no net change in steam velocity across the stage but with a decrease in both pressure and temperature, reflecting the work performed in the driving of the rotor.

text: Blade efficiency

text: Energy input to the blades in a stage:

text:
E
=

Δ
h

{\displaystyle E={\Delta h}}

 is equal to the kinetic energy supplied to the fixed blades (f) + the kinetic energy supplied to the moving blades (m).

text:
Or,

E

{\displaystyle {E}}

 = enthalpy drop over the fixed blades,

Δ

h

f

{\displaystyle {\Delta h_{f}}}

 + enthalpy drop over the moving blades,

Δ

h

m

{\displaystyle {\Delta h_{m}}}

.

text:
The effect of expansion of steam over the moving blades is to increase the relative velocity at the exit. Therefore, the relative velocity at the exit

V

r
2

{\displaystyle V_{r2}}

 is always greater than the relative velocity at the inlet

V

r
1

{\displaystyle V_{r1}}

.

text: In terms of velocities, the enthalpy drop over the moving blades is given by:

text:
Δ

h

m

=

V

r
2

2

−

V

r
1

2

2

{\displaystyle {\Delta h_{m}}={\frac {V_{r2}^{2}-V_{r1}^{2}}{2}}}

(it contributes to a change in static pressure)

text: The enthalpy drop in the fixed blades, with the assumption that the velocity of steam entering the fixed blades is equal to the velocity of steam leaving the previously moving blades is given by:

text:
Δ

h

f

{\displaystyle {\Delta h_{f}}}

 =

V

1

2

−

V

0

2

2

{\displaystyle {\frac {V_{1}^{2}-V_{0}^{2}}{2}}}

  where V0 is the inlet velocity of steam in the nozzle

text:
V

0

{\displaystyle V_{0}}

 is very small and hence can be neglected

text:
Therefore,

Δ

h

f

{\displaystyle {\Delta h_{f}}}

 =

V

1

2

2

{\displaystyle {\frac {V_{1}^{2}}{2}}}

text:
E
=

Δ

h

f

+
Δ

h

m

{\displaystyle E={\Delta h_{f}+\Delta h_{m}}}

text:
E
=

V

1

2

2

+

V

r
2

2

−

V

r
1

2

2

{\displaystyle E={\frac {V_{1}^{2}}{2}}+{\frac {V_{r2}^{2}-V_{r1}^{2}}{2}}}

text:
A very widely used design has half degree of reaction or 50% reaction and this is known as Parson’s turbine. This consists of symmetrical rotor and stator blades.
For this turbine the velocity triangle is similar and we have:

text:
α

1

=

β

2

{\displaystyle \alpha _{1}=\beta _{2}}

,

β

1

=

α

2

{\displaystyle \beta _{1}=\alpha _{2}}

text:
V

1

=

V

r
2

{\displaystyle V_{1}=V_{r2}}

,

V

r
1

=

V

2

{\displaystyle V_{r1}=V_{2}}

text: Assuming Parson’s turbine and obtaining all the expressions we get

text:
E

=

V

1

2

−

V

r
1

2

2

{\displaystyle {E}={V_{1}^{2}}-{\frac {V_{r1}^{2}}{2}}}

text:
From the inlet velocity triangle we have

V

r
1

2

=

V

1

2

+

U

2

−
2
U

V

1

cos

α

1

{\displaystyle {V_{r1}^{2}}={V_{1}^{2}+U^{2}-2UV_{1}\cos \alpha _{1}}}

text:
E

=

V

1

2

−

V

1

2

2

−

U

2

2

+

2
U

V

1

cos

α

1

2

{\displaystyle {E}={V_{1}^{2}-{\frac {V_{1}^{2}}{2}}-{\frac {U^{2}}{2}}+{\frac {2UV_{1}\cos \alpha _{1}}{2}}}}

text:
E

=

V

1

2

−

U

2

+
2
U

V

1

cos

α

1

2

{\displaystyle {E}={\frac {V_{1}^{2}-U^{2}+2UV_{1}\cos \alpha _{1}}{2}}}

text:
Work done (for unit mass flow per second):

W

=

U
∗
Δ

V

w

=

U
∗
(
2
∗

V

1

cos

α

1

−
U
)

{\displaystyle {W}={U*\Delta V_{w}}={U*(2*V_{1}\cos \alpha _{1}-U)}}

text: Therefore, the blade efficiency is given by

text:
η

b

=

2
U
(
2

V

1

cos

α

1

−
U
)

V

1

2

−

U

2

+
2

V

1

U
cos

α

1

{\displaystyle {\eta _{b}}={\frac {2U(2V_{1}\cos \alpha _{1}-U)}{V_{1}^{2}-U^{2}+2V_{1}U\cos \alpha _{1}}}}

text: Condition of maximum blade efficiency

text:
If

ρ

=

U

V

1

{\displaystyle {\rho }={\frac {U}{V_{1}}}}

, then

text:
(

η

b

)

m
a
x

=

2
ρ
(
cos

α

1

−
ρ
)

V

1

2

−

U

2

+
2
U

V

1

cos

α

1

{\displaystyle {(\eta _{b})_{max}}={\frac {2\rho (\cos \alpha _{1}-\rho )}{V_{1}^{2}-U^{2}+2UV_{1}\cos \alpha _{1}}}}

text:
For maximum efficiency

d

η

b

d
ρ

=
0

{\displaystyle {d\eta _{b} \over d\rho }=0}

, we get

text:
(
1
−

ρ

2

+
2
ρ
cos

α

1

)
(
4
cos

α

1

−
4
ρ
)
−
2
ρ
(
2
cos

α

1

−
ρ
)
(
−
2
ρ
+
2
cos

α

1

)
=
0

{\displaystyle {(1-\rho ^{2}+2\rho \cos \alpha _{1})(4\cos \alpha _{1}-4\rho )-2\rho (2\cos \alpha _{1}-\rho )(-2\rho +2\cos \alpha _{1})=0}}

text:
and this finally gives

ρ

o
p
t

=

U

V

1

=

cos

α

1

{\displaystyle {\rho _{opt}}={\frac {U}{V_{1}}}={\cos \alpha _{1}}}

text:
Therefore,

(

η

b

)

m
a
x

{\displaystyle {(\eta _{b})_{max}}}

 is found by putting the value of

ρ

=

cos

α

1

{\displaystyle {\rho }={\cos \alpha _{1}}}

 in the expression of blade efficiency

text:
(

η

b

)

r
e
a
c
t
i
o
n

=

2

cos

2

α

1

1
+

cos

2

α

1

{\displaystyle {(\eta _{b})_{reaction}}={\frac {2\cos ^{2}\alpha _{1}}{1+\cos ^{2}\alpha _{1}}}}

text:
(

η

b

)

i
m
p
u
l
s
e

=

cos

2

α

1

{\displaystyle {(\eta _{b})_{impulse}}={\cos ^{2}\alpha _{1}}}

text: Operation and maintenance[edit]

text: Because of the high pressures used in the steam circuits and the materials used, steam turbines and their casings have high thermal inertia. When warming up a steam turbine for use, the main steam stop valves (after the boiler) have a bypass line to allow superheated steam to slowly bypass the valve and proceed to heat up the lines in the system along with the steam turbine.  Also, a turning gear is engaged when there is no steam to slowly rotate the turbine to ensure even heating to prevent uneven expansion.  After first rotating the turbine by the turning gear, allowing time for the rotor to assume a straight plane (no bowing), then the turning gear is disengaged and steam is admitted to the turbine, first to the astern blades then to the ahead blades slowly rotating the turbine at 10–15 RPM (0.17–0.25 Hz) to slowly warm the turbine. The warm-up procedure for large steam turbines may exceed ten hours.[24]

text: During normal operation, rotor imbalance can lead to vibration, which, because of the high rotation velocities, could lead to a blade breaking away from the rotor and through the casing. To reduce this risk, considerable efforts are spent to balance the turbine. Also, turbines are run with high-quality steam: either superheated (dry) steam, or saturated steam with a high dryness fraction. This prevents the rapid impingement and erosion of the blades which occurs when condensed water is blasted onto the blades (moisture carry over).  Also, liquid water entering the blades may damage the thrust bearings for the turbine shaft.  To prevent this, along with controls and baffles in the boilers to ensure high-quality steam, condensate drains are installed in the steam piping leading to the turbine.

text: Maintenance requirements of modern steam turbines are simple and incur low costs (typically around $0.005 per kWh);[24]  their operational life often exceeds 50 years.[24]

text: Speed regulation[edit]

text: The control of a turbine with a governor is essential, as turbines need to be run up slowly to prevent damage and some applications (such as the generation of alternating current electricity) require precise speed control.[25] Uncontrolled acceleration of the turbine rotor can lead to an overspeed trip, which causes the governor and throttle valves that control the flow of steam to the turbine to close. If these valves fail then the turbine may continue accelerating until it breaks apart, often catastrophically. Turbines are expensive to make, requiring precision manufacture and special quality materials.

text: During normal operation in synchronization with the electricity network, power plants are governed with a five percent droop speed control. This means the full load speed is 100% and the no-load speed is 105%. This is required for the stable operation of the network without hunting and drop-outs of power plants. Normally the changes in speed are minor. Adjustments in power output are made by slowly raising the droop curve by increasing the spring pressure on a centrifugal governor. Generally this is a basic system requirement for all power plants because the older and newer plants have to be compatible in response to the instantaneous changes in frequency without depending on outside communication.[26]

text: Thermodynamics of steam turbines[edit]

text: The steam turbine operates on basic principles of thermodynamics using the part 3-4 of the Rankine cycle shown in the adjoining diagram. Superheated steam (or dry saturated steam, depending on application) leaves the boiler at high temperature and high pressure. At entry to the turbine, the steam gains kinetic energy by passing through a nozzle (a fixed nozzle in an impulse type turbine or the fixed blades in a reaction type turbine). When the steam leaves the nozzle it is moving at high velocity towards the blades of the turbine rotor. A force is created on the blades due to the pressure of the vapor on the blades causing them to move. A generator or other such device can be placed on the shaft, and the energy that was in the steam can now be stored and used. The steam leaves the turbine as a saturated vapor (or liquid-vapor mix depending on application) at a lower temperature and pressure than it entered with and is sent to the condenser to be cooled.[27] The first law enables us to find a formula for the rate at which work is developed per unit mass. Assuming there is no heat transfer to the surrounding environment and that the changes in kinetic and potential energy are negligible compared to the change in specific enthalpy we arrive at the following equation

text: where

text:
Ẇ is the rate at which work is developed per unit time
ṁ is the rate of mass flow through the turbine

text: Isentropic efficiency[edit]

text: To measure how well a turbine is performing we can look at its isentropic efficiency. This compares the actual performance of the turbine with the performance that would be achieved by an ideal, isentropic, turbine.[28]  When calculating this efficiency, heat lost to the surroundings is assumed to be zero. Steam's starting pressure and temperature is the same for both the actual and the ideal turbines, but at turbine exit, steam's energy content ('specific enthalpy') for the actual turbine is greater than that for the ideal turbine because of irreversibility in the actual turbine. The specific enthalpy is evaluated at the same steam pressure for the actual and ideal turbines in order to give a good comparison between the two.

text: The isentropic efficiency is found by dividing the actual work by the ideal work.[28]

text: where

text:
h3 is the specific enthalpy at state three
h4 is the specific enthalpy at state 4 for the actual turbine
h4s is the specific enthalpy at state 4s for the isentropic turbine

text: (but note that the adjacent diagram does not show state 4s: it is vertically below state 3)

text: Direct drive[edit]

text: Electrical power stations use large steam turbines driving electric generators to produce most (about 80%) of the world's electricity. The advent of large steam turbines made central-station electricity generation practical, since reciprocating steam engines of large rating became very bulky, and operated at slow speeds.  Most central stations are fossil fuel power plants and nuclear power plants; some installations use geothermal steam, or use concentrated solar power (CSP) to create the steam.  Steam turbines can also be used directly to drive large centrifugal pumps, such as feedwater pumps at a thermal power plant.

text: The turbines used for electric power generation are most often directly coupled to their generators.  As the generators must rotate at constant synchronous speeds according to the frequency of the electric power system, the most common speeds are 3,000 RPM for 50 Hz systems, and 3,600 RPM for 60 Hz systems.  Since nuclear reactors have lower temperature limits than fossil-fired plants, with lower steam quality, the turbine generator sets may be arranged to operate at half these speeds, but with four-pole generators, to reduce erosion of turbine blades.[29]

text: Marine propulsion[edit]

text: In steamships, advantages of steam turbines over reciprocating engines are smaller size, lower maintenance, lighter weight, and lower vibration. A steam turbine is only efficient when operating in the thousands of RPM, while the most effective propeller designs are for speeds less than 300 RPM; consequently, precise (thus expensive) reduction gears are usually required, although numerous early ships through World War I, such as Turbinia, had direct drive from the steam turbines to the propeller shafts. Another alternative is turbo-electric transmission, in which an electrical generator run by the high-speed turbine is used to run one or more slow-speed electric motors connected to the propeller shafts; precision gear cutting may be a production bottleneck during wartime.  Turbo-electric drive was most used in large US warships designed during World War I and in some fast liners, and was used in some troop transports and mass-production destroyer escorts in World War II.

text: The higher cost of turbines and the associated gears or generator/motor sets is offset by lower maintenance requirements and the smaller size of a turbine when compared to a reciprocating engine having an equivalent power, although the fuel costs are higher than a diesel engine because steam turbines have lower thermal efficiency. To reduce fuel costs the thermal efficiency of both types of engine have been improved over the years. Today, propulsion steam turbine cycle efficiencies have yet to break 50%, yet diesel engines routinely exceed 50%, especially in marine applications.[30][31][32] Diesel power plants also have lower operating costs since fewer operators are required. Thus, conventional steam power is used in very few new ships. An exception is LNG carriers which often find it more economical to use boil-off gas with a steam turbine than to re-liquify it.

text: Nuclear-powered ships and submarines use a nuclear reactor to create steam for turbines.  Nuclear power is often chosen where diesel power would be impractical (as in submarine applications) or the logistics of refuelling pose significant problems (for example, icebreakers). It has been estimated that the reactor fuel for the Royal Navy's Vanguard-class submarines is sufficient to last 40 circumnavigations of the globe – potentially sufficient for the vessel's entire service life. Nuclear propulsion has only been applied to a very few  commercial vessels due to the expense of maintenance and the regulatory controls required on nuclear systems and fuel cycles.

text: Early development[edit]

text: The development of steam turbine marine propulsion from 1894-1935 was dominated by the need to reconcile the high efficient speed of the turbine with the low efficient speed (less than 300 rpm) of the ship's propeller at an overall cost competitive with reciprocating engines. In 1894, efficient reduction gears were not available for the high powers required by ships, so direct drive was necessary. In Turbinia, which has direct drive to each propeller shaft, the efficient speed of the turbine was reduced after initial trials by directing the steam flow through all three direct drive turbines (one on each shaft) in series, probably totaling around 200 turbine stages operating in series. Also, there were three propellers on each shaft for operation at high speeds.[33] The high shaft speeds of the era are represented by one of the first US turbine-powered destroyers, USS Smith, launched in 1909, which had direct drive turbines and whose three shafts turned at 724 rpm at 28.35 knots.[34] The use of turbines in several casings exhausting steam to each other in series became standard in most subsequent marine propulsion applications, and is a form of cross-compounding. The first turbine was called the high pressure (HP) turbine, the last turbine was the low pressure (LP) turbine, and any turbine in between was an intermediate pressure (IP) turbine. A much later arrangement than Turbinia can be seen on RMS Queen Mary in Long Beach, California, launched in 1934, in which each shaft is powered by four turbines in series connected to the ends of the two input shafts of a single-reduction gearbox. They are the HP, 1st IP, 2nd IP, and LP turbines.

text: Cruising machinery and gearing[edit]

text: The quest for economy was even more important when cruising speeds were considered. Cruising speed is roughly 50% of a warship's maximum speed and 20-25% of its maximum power level.  This would be a speed used on long voyages when fuel economy is desired. Although this brought the propeller speeds down to an efficient range, turbine efficiency was greatly reduced, and early turbine ships had poor cruising ranges. A solution that proved useful through most of the steam turbine propulsion era was the cruising turbine. This was an extra turbine to add even more stages, at first attached directly to one or more shafts, exhausting to a stage partway along the HP turbine, and not used at high speeds. As reduction gears became available around 1911, some ships, notably the battleship USS Nevada, had them on cruising turbines while retaining direct drive main turbines. Reduction gears allowed turbines to operate in their efficient range at a much higher speed than the shaft, but were expensive to manufacture.

text: Cruising turbines competed at first with reciprocating engines for fuel economy. An example of the retention of reciprocating engines on fast ships was the famous RMS Titanic of 1911, which along with her sisters RMS Olympic and HMHS Britannic had triple-expansion engines on the two outboard shafts, both exhausting to an LP turbine on the center shaft. After adopting turbines with the Delaware-class battleships launched in 1909, the United States Navy reverted to reciprocating machinery on the New York-class battleships of 1912, then went back to turbines on Nevada in 1914. The lingering fondness for reciprocating machinery was because the US Navy had no plans for capital ships exceeding 21 knots until after World War I, so top speed was less important than economical cruising. The United States had acquired the Philippines and Hawaii as territories in 1898, and lacked the British Royal Navy's worldwide network of coaling stations. Thus, the US Navy in 1900-1940 had the greatest need of any nation for fuel economy, especially as the prospect of war with Japan arose following World War I. This need was compounded by the US not launching any cruisers 1908-1920, so destroyers were required to perform long-range missions usually assigned to cruisers. So, various cruising solutions were fitted on US destroyers launched 1908-1916. These included small reciprocating engines and geared or ungeared cruising turbines on one or two shafts. However, once fully geared turbines proved economical in initial cost and fuel they were rapidly adopted, with cruising turbines also included on most ships. Beginning in 1915 all new Royal Navy destroyers had fully geared turbines, and the United States followed in 1917.

text: In the Royal Navy, speed was a priority until the Battle of Jutland in mid-1916 showed that in the battlecruisers too much armour had been sacrificed in its pursuit. The British used exclusively turbine-powered warships from 1906. Because they recognized that a significant cruising range would be desirable given their worldwide empire, some warships, notably the Queen Elizabeth-class battleships, were fitted with cruising turbines from 1912 onwards following earlier experimental installations.

text: In the US Navy, the Mahan-class destroyers, launched 1935–36, introduced double-reduction gearing. This further increased the turbine speed above the shaft speed, allowing smaller turbines than single-reduction gearing. Steam pressures and temperatures were also increasing progressively, from 300 psi/425 F (2.07 MPa/218 C – saturation temperature) on the World War I-era Wickes class to 615 psi/850 F (4.25 MPa/454 C) superheated steam on some World War II Fletcher-class destroyers and later ships.[35][36] A standard configuration emerged of an axial-flow high-pressure turbine (sometimes with a cruising turbine attached) and a double-axial-flow low-pressure turbine connected to a double-reduction gearbox. This arrangement continued throughout the steam era in the US Navy and was also used in some Royal Navy designs.[37][38] Machinery of this configuration can be seen on many preserved World War II-era warships in several countries.[39] When US Navy warship construction resumed in the early 1950s, most surface combatants and aircraft carriers used 1,200 psi/950 F (8.28 MPa/510 C) steam.[40] This continued until the end of the US Navy steam-powered warship era with the Knox-class frigates of the early 1970s. Amphibious and auxiliary ships continued to use 600 psi (4.14 MPa) steam post-World War II, with USS Iwo Jima, launched in 2001, possibly the last non-nuclear steam-powered ship built for the US Navy.

text: Turbo-electric drive[edit]

text: Turbo-electric drive was introduced on the battleship USS New Mexico, launched in 1917. Over the next eight years the US Navy launched five additional turbo-electric-powered battleships and two aircraft carriers (initially ordered as Lexington-class battlecruisers). Ten more turbo-electric capital ships were planned, but cancelled due to the limits imposed by the Washington Naval Treaty. Although New Mexico was refitted with geared turbines in a 1931-33 refit, the remaining turbo-electric ships retained the system throughout their careers. This system used two large steam turbine generators to drive an electric motor on each of four shafts. The system was less costly initially than reduction gears and made the ships more maneuverable in port, with the shafts able to reverse rapidly and deliver more reverse power than with most geared systems. Some ocean liners were also built with turbo-electric drive, as were some troop transports and mass-production destroyer escorts in World War II. However, when the US designed the "treaty cruisers", beginning with USS Pensacola launched in 1927, geared turbines were used to conserve weight, and remained in use for all fast steam-powered ships thereafter.

text: Current usage[edit]

text: Since the 1980s, steam turbines have been replaced by gas turbines on fast ships and by diesel engines on other ships; exceptions are nuclear-powered ships and submarines and LNG carriers.[41] Some auxiliary ships continue to use steam propulsion. In the U.S. Navy, the conventionally powered steam turbine is still in use on all but one of the Wasp-class amphibious assault ships. The Royal Navy decommissioned its last conventional steam-powered surface warship class, the Fearless-class landing platform dock, in 2002. In 2013, the French Navy ended its steam era with the decommissioning of its last Tourville-class frigate. Amongst the other blue-water navies, the Russian Navy currently operates steam-powered Kuznetsov-class aircraft carriers and  Sovremenny-class destroyers. The Indian Navy currently operates INS Vikramaditya, a modified Kiev-class aircraft carrier; it also operates three Brahmaputra-class frigates commissioned in the early 2000s and one Godavari-class frigate scheduled for decommissioning. The Chinese Navy currently operates steam-powered Kuznetsov-class aircraft carriers, Sovremenny-class destroyers along with Luda-class destroyers and the lone Type 051B destroyer.

text: Most other naval forces either retired or re-engined their steam-powered warships by 2010. As of 2017, the Mexican Navy operates four steam-powered former U.S. Knox-class frigates and two steam-powered former U.S. Bronstein-class frigates. The Egyptian Navy and the Republic of China Navy respectively operate two and six former U.S. Knox-class frigates. The Ecuadorian Navy currently operates two steam-powered Condell-class frigates (modified Leander-class frigates).

text: Locomotives[edit]

text: A steam turbine locomotive engine is a steam locomotive driven by a steam turbine.

text: The main advantages of a steam turbine locomotive are better rotational balance and reduced hammer blow on the track. However, a disadvantage is less flexible output power so that turbine locomotives were best suited for long-haul operations at a constant output power.[42]

text: The first steam turbine rail locomotive was built in 1908 for the Officine Meccaniche Miani Silvestri Grodona Comi, Milan, Italy. In 1924 Krupp built the steam turbine locomotive T18 001, operational in 1929, for Deutsche Reichsbahn.

text: Testing[edit]

text: British, German, other national and international test codes are used to standardize the procedures and definitions used to test steam turbines. Selection of the test code to be used is an agreement between the purchaser and the manufacturer, and has some significance to the design of the turbine and associated systems. In the United States, ASME has produced several performance test codes on steam turbines. These include ASME PTC 6-2004, Steam Turbines, ASME PTC 6.2-2011, Steam Turbines in Combined Cycles, PTC 6S-1988, Procedures for Routine Performance Test of Steam Turbines. These ASME performance test codes have gained international recognition and acceptance for testing steam turbines. The single most important and differentiating characteristic of ASME performance test codes, including PTC 6, is that the test uncertainty of the measurement indicates the quality of the test and is not to be used as a commercial tolerance.[43]


document_title: Mo Farah

question_text: where did mo farrah come in london marathon

question_tokens: where did mo farrah come in london marathon

root

text: Mo Farah

text: Early life and education[edit]

text: Mohamed Muktar Jama Farah was born on 23 March 1983 in Gabiley, Somaliland.[18][19][20] Although Farah's family was originally from Gabiley, they were living in Mogadishu, Somalia as his father was a businessman there.[19] His family had to flee Mogadishu since they were targeted due to their origin from Somaliland, which had declared independence from Somalia.[19] After fleeing from Mogadishu to Gabiley, Somaliland with his family,[21] Farah then spent his early childhood as a refugee in Djibouti with his twin brother.[22] He moved to Britain at the age of eight to join his father, speaking barely a word of English.[22][23] His grandfather, Jama, was born in the British protectorate of Somaliland.[24] His father, Mukhtar Farah, is an IT consultant and a British citizen, who was born in London, England and grew up in Hounslow.[25][26][27]

tag: p

text: Farah attended Isleworth and Syon School, and Feltham Community College. His athletic talent was first identified by physical education teacher Alan Watkinson.[28] Farah's ambition was to become a car mechanic or play as a right winger for Arsenal football club.[29] He later joined the Borough of Hounslow Athletics Club in west London.[30][31]

text: Junior career[edit]

text: Farah represented Hounslow at cross-country in the London Youth Games.[32] In 1996, at the age of 13, he entered the English schools cross-country and finished ninth. The following year he won the first of five English school titles.[28] Recognising his talent, athletics philanthropist Eddie Kulukundis paid the legal fees to complete Farah's naturalisation as a British citizen, allowing Farah to travel to competitions without visa issues.[33][34]

text: Farah's first major title was at 5000 metres at the European Athletics Junior Championship in 2001,[35] the same year that he began training at St Mary's University College, Twickenham. That year, Farah became one of the first two athletes in the newly formed Endurance Performance Centre at St Mary's. He lived and trained at the College, and took some modules in an access course before becoming a full-time athlete as his career progressed.

text: Senior career[edit]

text: 2005–2008: First titles and personal bests[edit]

text: In 2005, Farah moved in with Australian Craig Mottram and a group of Kenyan runners that included 10,000 m world number one Micah Kogo. "They sleep, eat, train and rest, that's all they do but as an athlete you have to do all those things. Running with Craig made me feel more positive," Farah said. "If I ever want to be as good as these athletes I've got to work harder. I don't just want to be British number one, I want to be up there with the best."[28]

text: In July 2006, Farah recorded a time of 13 minutes 9.40 seconds for 5000 m to become Britain's second-fastest runner after Dave Moorcroft. A month later, Farah won the silver medal in the European Championship 5000m in Gothenburg. Coaches Alan Storey and Mark Rowland made sure that Farah remained competitive and a few words from Paula Radcliffe before the 5000 m final inspired Farah. He has stated that: "She said to me, 'Go out and be brave. Just believe in yourself'."[28] In December 2006, Farah won the 2006 European Cross Country Championships in San Giorgio su Legnano, Italy.[36]

text: Farah represented the UK at 5000 m in the 2007 World Championships in Osaka, Japan. Farah finished sixth in a time of 13:47.54.[37][38]

text: In May 2008, Farah ran 10,000 m events, which was the fastest UK men's time for almost eight years. However, he was knocked out before the 5000 m final at the 2008 Olympics in Beijing.

text: 2009–2010: British records and European champion[edit]

text: In January 2009, Farah set a new British indoor record in the 3000 metres, breaking John Mayock's record with a time of 7 minutes 40.99 seconds in Glasgow.[39] A few weeks later, he broke his own record by more than six seconds with a time of 7 minutes 34.47 at the UK Indoor Grand Prix in Birmingham,[40] a performance which commentator Steve Cram called "the best performance by a male British distance runner for a generation".[41] Farah attributed his good form to a spell of winter training at altitude in Ethiopia and Kenya.[42] In March 2009 he took gold in the 3000 m at the European Indoor Championships in Turin, recording a time of 7 minutes 40.17.[43]

text: Farah competed at the 2009 World Championships in Athletics: he was in the leading pack early on in the 5000 metres race and eventually finished seventh – the best by a European runner. After the championships, he scored a victory in his first road competition over 10 miles, winning the Great South Run in 46:25 to become the third fastest Briton in spite of strong winds.[44]

text: Farah was one of the favourites to upset Serhiy Lebid's dominance at the 2009 European Cross Country Championships.[45] However, Lebid was never in contention as Farah and Alemayehu Bezabeh were some distance ahead throughout the run. Farah was overtaken by Bezabeh in the latter stages of the race, leaving the Briton with a second consecutive silver medal at the competition.[46] He did not manage to attend the medal ceremony, however, as he collapsed immediately after the race and needed medical attention.[47] After a close third place behind Edwin Soi at the BOclassic,[48] Farah competed in the short course race at the Great Edinburgh Cross Country. He was the favourite to win and surged ahead to build a comfortable lead. However, he appeared tired in the latter stages and finished third behind British runners Ricky Stevenson and Steve Vernon. Farah again required post-race medical attention and subsequent tests revealed he had low levels of iron and magnesium. He was prescribed supplements for the condition and his high altitude training plans in Kenya were unaffected.[49]

text: Farah won the 2010 London 10,000 in late May in a time of 27:44, in the process beating 10K world record holder Micah Kogo.[50] His success continued the following week at the European Cup 10,000 m. There, he improved his track best by nearly 16 seconds, finishing in a time of 27:28.86. Farah won by a margin of over forty seconds ahead of second placed Abdellatif Meftah.[51] After training in Africa, he returned to Europe for the 2010 European Athletics Championships. He took the 10,000 metres gold medal, overtaking Ayad Lamdassem with two laps to go and finishing the race unpressured in a time of 28:24.99. This was Farah's first major title and also the first European gold medal in the event for Great Britain.[52] He then went on to win the 5000 m from Jesus España, becoming only the fifth man in the 66-year history of the European Championships to achieve the 5000 m/10,000 m double, and the first for 20 years, following in the footsteps of the Czech Emil Zátopek in 1950, Zdzislaw Krzyszkowiak of Poland in 1958, Finland's Juha Vaatainen in 1971 and Salvatore Antibo, of Italy, in 1990.[53][54]

text: On 19 August 2010, at a Diamond League meeting in Zürich, Farah ran 5000 m in 12:57.94, breaking David Moorcroft's long-standing British record and becoming the first ever British athlete to run under 13 minutes.[55]

text: In December 2010, Farah was named track-and-field athlete of the year by the British Olympic Association.[56] He closed the year at the BO classic and just missed out on the 10,000 m title, losing to Imane Merga in a sprint finish by 0.2 seconds.[57]

text: 2011-12: European and British records, and world medals[edit]

text: 2011 was a successful year for Farah, beginning on 8 January at the Edinburgh Cross Country, where he defeated the top four finishers of that year's European Championships to take victory in the long race.[58]

text: In February 2011, Farah announced that he would be relocating to Portland, Oregon to work with new coach Alberto Salazar, train alongside Galen Rupp, and avoid the attention of the British tabloids.[2][59] On 19 February 2011 in Birmingham, England, Farah broke the European 5000 m indoor record with a time of 13:10.60, at the same time taking ten seconds off the 29-year-old British indoor record of Nick Rose.[60] On 5 March 2011, he won gold in the 3000 metres at the European Indoor Championships. On 20 March, Farah also won the NYC Half Marathon in a time of 1:00:23, a new British record.[61][62] He and training partner Galen Rupp had originally planned on running a 10,000 m race in New Zealand. However, after the race was cancelled due to the Christchurch earthquake and damage done to the track, they entered the half-marathon in New York.

text: On 3 June 2011, at a Diamond League meeting in Eugene, Oregon, Farah won the Prefontaine Classic's 10,000 m event in 26:46.57, setting a new British and European record.[63] On 22 July 2011, at a Diamond League meeting in Monaco, he set a new British national record in the 5000 m with a time of 12:53.11.[64] Farah edged out American Bernard Lagat to win the race.[64]

text: In the 2011 World Championships in Athletics in Daegu, South Korea, Farah made a major breakthrough on the world stage by taking the silver medal in the 10,000 m and then the gold in the 5000 m.[65] He became the first British man to win a World Championships medal over either distance.[66] Farah had in fact been more strongly favoured to take the 10,000 m title, but was narrowly beaten in a last lap sprint by Ethiopian Ibrahim Jeilan. In the 5000 m, he overcame Lagat, beating him into second place. Following the race, Dave Moorcroft, former 5000 metres world record holder, hailed Farah as "the greatest male distance runner that Britain has ever seen".[67]

text: At the European Championships in June 2012, he won the 5000m. This then made Farah the first athlete to win this European title more than once.[68]

text: 2012: Double Olympic champion[edit]

text: At the London 2012 Olympics, on 4 August, Farah won the 10,000 m gold in a time of 27:30.42. This was Great Britain's first Olympic gold medal in the 10,000 m, and came after two other gold medals for the country in the same athletics session.[69][70] His training partner, Galen Rupp of the United States, took second place. Both runners are coached by Alberto Salazar. Farah stated that he would observe his Ramadan fast later in the year.[71] On 11 August 2012, Farah made it a long-distance double, winning the 5000 metres in a time of 13:41.66.[72] The noise from the crowd in the 5,000 m race was so loud it made the camera shake and distorted the photo-finish image.[73] He dedicated the two golds to his twin daughters.

text: On 23 August 2012, Farah returned to the track at a Diamond League meet in Birmingham, where he capped off a winning season with another victory over a distance of two miles (3.2 km).[74]

text: CBE[edit]

text: Following his 2012 successes, Farah was appointed Commander of the Order of the British Empire (CBE) in the 2013 New Year Honours for services to athletics.[75][76] The move was met with anger by many in the general public, including erstwhile Minister of Sports Gerry Sutcliffe, who felt that Farah instead deserved a higher accolade.[77][78] Farah's former physical education teacher Alan Watkinson similarly indicated that he was disappointed that Farah was not knighted and that the decision "discredits the system although it's still a fantastic achievement for Mo and well deserved."[78] However, deputy Prime Minister Nick Clegg cited Farah's Olympic double gold win in his 2013 New Year's message and 2012 Autumn conference,[79][80] and David Cameron on August 2013 expressed support for a knighthood for Mo Farah.[81]

text: 2013: 1500 m record and world medals[edit]

text: On 19 July 2013, at the Herculis meeting in Monaco, Farah broke the European 1500 m record with a time of 3:28.81. The feat meant that he was the sixth fastest man ever over the distance, overtaking Steve Cram's 28-year-old British record and Fermín Cacho's 16-year-old European record.[82] It also made Farah the seventh man, behind Saïd Aouita, Daniel Komen, Ali Saïdi-Sief, Hicham El Guerrouj, Augustine Kiprono Choge and Bernard Lagat to break both the 3:30 barrier in the 1500 metres and the 13-minute barrier in the 5000 metres, as well as the only athlete in history to run sub 3:30, sub 13-minute and sub 27-minute for 1500 metres, 5000 metres and 10,000 metres respectively. Additionally, he has a sub 1 hour run in the half-marathon.

text: The following month, Farah won the London Diamond League Anniversary Games' 3000 metres event in a time of seven minutes and 36.85 seconds.[83] He twice broke the national record in the half-marathon, first on 24 February in New Orleans, then broke his own record on 15 September in the Bupa Great North run.

text: On 10 August 2013, Farah stayed in front of Ibrahim Jeilan to win the 10,000 m event at the World Championships in Moscow. The victory was his fourth global title.[84] On 16 August 2013, Farah won the 5,000 m event, in the process becoming double world and Olympic champion.[85] After this victory, BBC commentator Brendan Foster and Sebastian Coe called Farah 'Britain's greatest ever athlete'.[86] Farah became only the second man in history to win long-distance titles at successive editions of the Olympics and World Championships, after Kenenisa Bekele's 2008–09 feat.[87] He was the first British athlete to win two individual gold medals at a World Championships.[84][88][89]

text: In December 2013, Farah was the second favourite, behind Wimbledon tennis champion Andy Murray, to become the BBC Sports Personality of the Year. When he was asked what drove him to keep pushing back the boundaries of athletic accomplishment, he noted sprinter Usain Bolt's record breaking streak as a motivating example of what is possible for all dedicated athletes.[90]

text: Farah was a finalist for the 2013 IAAF World Athlete of the year award. In preparation for his marathon debut, he also extended his training schedule to 120 miles a week.[14]

text: 2014: Double gold in Zürich[edit]

text: Farah began 2014 preparing for the year's London Marathon, his first such run. He described running the event as a longstanding ambition of his, particularly to do so in London.[91] Farah finished in eighth place in a time of 2:08.21. This was outside Steve Jones' GB record, but set a new English national record.[92]

text: Farah was due to compete at the 2014 Commonwealth Games in Glasgow. However, he withdrew due to illness from a stomach ailment and an infection caused from having a tooth removed.[93] Farah later appeared in Zürich at the 2014 European Athletics Championships. He successfully defended his 5000 m title and won a gold in the 10,000 m, thus completing another major championship double.[94] This made him the most successful individual in the history of the European Athletics Championships, with five titles to his name.[95]

text: On 7 September 2014, Farah competed in the Great North Run, a British half marathon. He won the race with a personal best time of 1:00:00, exactly 1 hour.[96]

text: 2015: World and European records[edit]

text: On 21 February 2015, Farah broke the indoor two-mile world record at the Birmingham Indoor Grand Prix. He ran an 8:03.4 to break Kenenisa Bekele's record.[97]

text: On 22 March 2015, Farah broke the European record for half marathon in Lisbon. He ran a time of 59 minutes, 32 seconds, 20 seconds, surpassing the record set 14 years previously by Spain's Fabián Roncero.[98]

text: He repeated his long-distance gold medal double at the 2015 World Championships in Athletics.[99] His win in the 10,000m made him the oldest World Championship winner in that event, at age 32.[100]

text: 2016: Double-Double Olympic Golds at Rio[edit]

text: On 26 March, Farah received a bronze medal in the 2016 IAAF World Half Marathon Championships in Cardiff, finishing in 59:59, less than one second ahead of Abayneh Ayele.[101][102] On 20 February, Farah won the Glasgow Indoor Grand Prix 3000m event.[103] On 5 June 2016, Farah broke the 34-year-old British 3000 metre record set by Moorcroft by winning the Diamond League in Birmingham, a win he dedicated to the recently deceased boxer Muhammad Ali.[104] In July 2016 Farah set the concurrent world-leading time in the 5000m in winning the Diamond League in London.[105] He won the 10,000m at the Diamond League in Eugene, in a time of 26:53.71 which remained the second-fastest time in the world of the year.[106]

text: On 13 August, Farah won a gold medal in the 10,000 metres at the Rio Olympics, making it the first time a Briton had won three athletic gold Olympic medals.[107] After being accidentally clipped on the back of the heel by American Galen Rupp on the 10th lap he fell,[108] but went on to win gold with the time of 27:05.17. Rupp slowed after Farah's fall to check his condition and finished in 5th place with a time of 27:08.92. In the final lap Farah battled Paul Tanui, who took the lead with 300 metres remaining. Farah edged him out with 100 metres to go. Tanui finished in second place with a time of 27:05.64.[108]

text: On 20 August, Farah went on to win a second gold medal in the 5,000 metres at the Rio Olympics. Coming into the 31st Olympiad, Farah was trying to win gold medals in the 10,000 metres and 5,000 metres to double his success from the London Olympics. Farah held off the lead he had set and finished with a time of 13.03.30, making it only the second time someone has retained the 5000m and 10,000m Olympic titles, after Lasse Virén of Finland in 1972 and 1976.[109] In September 2016, he won the Great North Run for a record third consecutive year.[110]

text: In 2016, he was the fastest person from the European continent over two middle distance events and three long-distance events; the 1500 metres, 3000 metres, 5000 metres, 10,000 metres and the half-marathon respectively.[111] His ninth global title, the 5000m in Rio, made him surpass Kenenisa Bekele as the most frequent winner of gold in history for major long-distance events. He remained unbeaten in 2016 in the 3000m as well as in six races over the 10,000m and 5,000m distances.[112] Farah's distance double was voted the second most memorable TV moment of the year by British voters according to an ASDA poll.[113]

text: 2017 and 2018[edit]

text: Farah announced that he would switch from track events to the marathon after the 2017 World Championships in Athletics.[114] He won the 10,000m event, and came 2nd in the 5,000m event after Ethiopia's Muktar Edris.[115][116]

text: Farah won his final two track events, in the Diamond league, in Birmingham and Zurich.[117][118] On 24 August 2017, he won his final 5,000m in the Diamond league, finishing in 13:06.05, in a final sprint against Paul Chelimo and Muktar Edris just behind in 13:06.09.[118][119]

text: On 10 September 2017, Farah won the Great North Run for a record fourth consecutive time.[120] He finished in 1:00:06, 6 seconds ahead of Jake Robertson.[121]

text: On 31 October, Farah split from Alberto Salazar in order to be coached by Gary Lough, husband and former coach of Paula Radcliffe. Salazar stated that the split was mutual and he would be happy to advise Farah in the future.[122]

text: On 22 April 2018 Farrah came third the London Marathon in a time of 2:06:22, comfortably beating the GB record of 2:07:13 set by Steve Jones in 1985.[123][124]

text: "Mobot"[edit]

text: Farah often marks victories with a celebration dance known as the "Mobot". He adopted the move following a television appearance in May 2012 opposite sports presenter Clare Balding, on the panel game show A League of Their Own. The host James Corden suggested to the panelists that they should think of a new dance to mark Farah's winning celebration, and Balding subsequently came up with the "M" gesture called "Mobot". While demonstrating it for the first time, she indicated that the part of the move intended to represent the "M" in "Mo" was inspired by the dance to "YMCA", a popular song by the Village People. Corden himself then named it as the "Mobot".[125] A robot was named "Mobot" at a university research exhibition, in honour of Farah's celebration.[126] Farah has since used the pose as part of a charity to raise funds for his foundation. Virgin Media has promised to donate £2 for every YouTube video that is uploaded with someone doing the mobot.[127] Farah often uses the sign-off Shabba in online postings.[128]

text: Personal life[edit]

text: Family and interests[edit]

text: Farah has a twin brother, Hassan, who lives in Somalia. They were separated at eight years old, when Mo, his two younger brothers, and his mother joined their father, who had been working and studying in the UK. Hassan, however, was unwell and unable to travel, so stayed behind with family in Djibouti. When Farah's father returned to collect Hassan, the family he was living with had moved and could not be found. Farah and his twin ended up being separated for twelve years. Hassan is now a telecoms engineer with a wife and five children. Farah has a third younger brother, who was also born after the family's move to London.[129]

text: In April 2010, Farah married his longtime girlfriend Tania Nell in Richmond, London. Other athletes at the wedding included Paula Radcliffe, Steve Cram, Hayley Yelling, Jo Pavey, Mustafa Mohamed and Scott Overall, who was an usher.[130][131] Farah has a stepdaughter named Rihanna from this relationship.[132] He and his wife have twin daughters called Aisha and Amani, born in August 2012.[133] In 2015, Farah and Nell had a son called Hussein.

text: Farah is a Muslim,[134] and is an active supporter of the Muslim Writers Awards.[135] Islam is an important part of his preparation: "I normally pray before a race, I read dua [Islamic prayers or invocations], think about how hard I've worked and just go for it." He notes that "the Qur'an says that you must work hard in whatever you do, so I work hard in training and that's got a lot to do with being successful. [It] doesn't just come overnight, you've got to train for it and believe in yourself; that's the most important thing."[136] An RISSC publication named Farah as among the 500 most influential Muslims in the world in 2013.[137]

text: Farah is also a fan of Arsenal F.C., and has trained with its first team squad.[138][139] He has indicated a desire to become a fitness coach at the Emirates Stadium in Holloway[140] once he retires so as to improve its conditioning record.[139] In October 2013, he launched a book titled Mo Farah, Twin Ambitions: My autobiography in Canary Wharf, London.[141]

text: Farah has a large following on social media. This includes roughly 1.5 million followers on Twitter and 1.1 million on Facebook. In 2013, he was the top-ranked query for a sportsperson on the search engine Microsoft UK Bing who was not a footballer.[142]

text: As of January 2014, Farah's main residence is of Portland, Oregon, where he and his family have a home.[143] However, on The Jonathan Ross Show in September 2017, he revealed that he planned to move back to the UK.[144]

text: Philanthropy[edit]

text: Farah is additionally involved in various philanthropic initiatives, launching the Mo Farah Foundation after a trip to Somalia in 2011.[145] The following year, he participated in ITV's The Cube and won £250,000 for his foundation, becoming the first and only person to win the top prize on the show.[146] Along with other high-profile athletes, Farah later took part in the 2012 Olympic hunger summit at 10 Downing Street hosted by Prime Minister David Cameron, part of a series of international efforts which have sought to respond to the return of hunger as a high-profile global issue.[147]

text: Olympic memorabilia featuring and signed by Farah has also been auctioned off to raise funds for the London Organising Committee of the Olympic and Paralympic Games (LOCOG).[148] In 2013, he joined legislators and activists in a campaign urging Barclays Bank to repeal its decision to withdraw from the UK remittance market. Farah often used money transfer operators to send remittances to family, and some of the world's largest organisations and charities, including the UN and his own foundation, likewise paid staff and channelled funds through these services.[149] In March 2013, Farah, singer Robbie Williams, and a number of other celebrities also urged Chancellor George Osborne to clamp down on global corporations that avoid paying taxes in poor countries in which they operate.[150] He has also expressed support for research into brain tumours.[151]

text: On August 7, 2017, Farah became a global ambassador for Marathon Kids. Speaking of his new role, Farah said, "I love running, and it's given me and my family so much. As a dad, I know how important it is for my children to be active, and I'm honoured to have the chance to inspire kids to run with Marathon Kids."[152]

text: Endorsements, advertising and sponsorships[edit]

text: Farah has endorsement deals with a number of companies, including PACE Sports Management, Nike, Lucozade, Quorn, Bupa and Virgin Media.[145] His work with Nike Inc. includes training at the Nike Oregon Project and marketing of clothing and shoes.[153][154][155] In order to preserve his earnings after taxes, Farah also applied in 2013 to have his main place of residence changed to Portland, where he spends most of the year training.[143]

text: In December 2013, Farah signed a marketing deal with Quorn, part of a multi-million pound campaign aimed at doubling the firm's sales. He led television advertisements for Quorn's vegetarian forms of protein, with the campaign scheduled to last throughout the following year.[156]

text: Travel security[edit]

text: In 2012–2013, Farah intimated that he had been stopped a number of times by U.S. Customs officials under suspicion of being a terrorist, which he attributed to confusion between his full name "Mohamed" and a computerised check-in process.[157] On one occasion after the 2012 Olympics, he said that he had attempted to prove his identity by showing his Olympic gold medals to customs officials, but that this was not accepted.[158]

text: After U.S. President Donald Trump signed an executive order temporarily suspending the immigration of Somali-born U.S. permanent residents, Farah made a statement on his Facebook account stating that "I will have to tell my children that Daddy might not be able to come home."[159]

text: In March 2018, Farah posted a video on Instagram depicting what he alleges to be racial harassment at Munich Airport.[160]

text: Missed drug tests[edit]

text: In 2010 and early 2011, Farah missed two drug tests in a twelve-month period.[161][162] A third missed test would have resulted in an anti-doping rule violation.[163]

text: Blood test[edit]

text: In summer 2015, Farah provided a public blood test in an effort to dispel concerns following various events, including pictures posted to Facebook by Hamza Driouch, who is banned from competing for doping violations, which showed him training with Farah.[164] Farah was seen running directly in front of Driouch during a training session. Management for Mo Farah suggested, however, that the training session was merely Farah employing local athletes to pace him and that he does not have any control over who joins in the training session. Hamza Driouch has been officially banned from attending training sessions in any capacity for two years from 31 December 2014.[165] In June 2015, in a BBC Panorama documentary, it was alleged that Farah's coach Alberto Salazar was guilty of doping offences at the Nike Oregon Project. The programme did not accuse Farah of any wrongdoing.[166] On 6 June 2015 Farah held a press conference in which he expressed his anger that his name was "being dragged through mud". He withdrew from a 1500 metres event at the Birmingham Diamond League race on 7 June, describing himself as "emotionally and physically drained".[167] Farah said he had been told by Salazar he was not involved in Mary Slaney's career at the time she tested positive for testosterone but this version of Salazar's history has been challenged.[168]

text: In February 2017 Farah issued a statement in which he claimed to be a "clean athlete" after a leaked report suggested his American coach, Alberto Salazar, may have broken anti-doping rules to boost the performance of some of his athletes.[169]

text: Awards and honours[edit]

text: Athletics[edit]

text:
2006 British Athletics Writers' Association Award[170]
2010 British Athletics Writers' Association Award[170]
2010 Best Senior Athlete of 2010 (UK Aviva Athletics Awards)[171]
2010 London Youth Games Hall of Fame[172]
2011 British Athletics Writers' Association Award[135]
2011 European Athlete of the Year[135][173]
2011 BBC Sports Personality of the Year Award, 3rd place
2011 Athletics Weekly International Male Athlete
2012 British Athletics Writers' Association Award[174]
2012 European Athlete of the Year[175]
2012 Laureus World Sports Award for Breakthrough of the Year, nominee
2012 Athletics Weekly International Male Athlete
2013 IAAF World Athlete of the Year, finalist
2013 British Athletics Writers' Association Award[170]
2013 Athletics Weekly International Male Athlete[176]
2013 Laureus World Sports Award for Sportsman of the Year, nominee
2013 British Olympic Association Olympic athlete of the year[177]
2013 AIPS Europe Sportsmen of the Year – Frank Taylor Trophy
2013 Rodale, Inc., Running Times – Runner of the Year[178]
2014 Jesse Owens International Athlete Trophy, nominee[179]
2014 Laureus World Sports Award for Sportsman of the Year, nominee
2015 World Record, 2-mile run, Birmingham
Runners World top 50 influential individuals in running[180]
LetsRun.com number 1 in 2015 year end world ranking for long distance runners[181]
2015 fastest men's 10,000-meter runner[182]
2016 BAWA Athlete of the Year[183]
2016 British Athletics Supporters Club athlete of the year[184]
2016 Athletics Weekly International Male Athlete of the Year, ahead of Usain Bolt[185]
2016 Athletics Weekly British Male Athlete of the Year[185]
2017 Sportsman of the Year at the Lycamobile British Ethnic Diversity Sports Awards (BEDSAs)[186][187][188]
2017 BBC Sports Personality of the Year Award, 1st place

tag: ul

text: Other[edit]

text:
2013 Commander of the Most Excellent Order of the British Empire (CBE)[76]
2013 Premier Inn Celebrity Dad of The Year[189]
2013 Best at Sport award at the British Muslim Awards[190]
6th place, Freuds Heroes Index[191]
2014 World's 100 Most Powerful Arabs, Arabian Business[192]
2015, clothing firm Rohan's 8th greatest Briton of all time[193]
2015 Evening Standard's top 25 most influential Londoners[194]
2016 Sports Relief highest polled sporting London hero with 27% of the vote[195]
2016, Nickelodeon Kids' Choice Award for Inspirational Athlete.[196]
2016, 5th most powerful Black Briton, on 10th anniversary of Powerlist, African and Caribbean heritage listing[197]
2017, Created a Knight Bachelor for services to Athletics.[198]

text: National titles[edit]

text:
British Athletics Championships
5000 metres: 2007, 2011
British Indoor Athletics Championships
3000 metres: 2007
British 10K Championships
10K run: 2011, 2012
British Marathon Championships
Marathon: 2014

text: Race results[edit]

text: All information from Association of Road Racing Statisticians.[199]

text: International competitions[edit]

text:
Year

Competition

Venue

Position

Event

Notes

1999

World Youth Championships

Bydgoszcz, Poland

6th

3000 m

8:21.25

European Cross Country Championships

Velenje, Slovenia

5th

Junior individual

23:18

1st

Junior team

26 pts

2000

World Cross Country Championships

Vilamoura, Portugal

25th

Junior individual

24:37

12th

Junior team

216 pts

World Junior Championships

Santiago, Chile

10th

5000 m

14:12.21

European Cross Country Championships

Malmö, Sweden

7th

Junior individual

19:12

2nd

Junior team

25 pts

2001

World Cross Country Championships

Oostende, Belgium

59th

Junior individual

28:06

15th

Junior team

332 pts

European Junior Championships

Grosseto, Italy

1st

5000 m

14:09.91

European Cross Country Championships

Thun, Switzerland

2nd

Junior individual

19:38

1st

Junior team

54 pts

2003

World Cross Country Championships

Lausanne, Switzerland

74th

Short race

12:13

European U23 Championships

Bydgoszcz, Poland

2nd

5000 m

13:58.88

2005

European Indoor Championships

Madrid, Spain

6th

3000 m

7:54.08

World Cross Country Championships

Saint-Galmier, France

37th

Senior race

37:50

17th

Senior team

308 pts

European Cup

Florence, Italy

2nd

3000 m

8:17.28

European U23 Championships

Erfurt, Germany

2nd

5000 m

14:10.96

European Cross Country Championships

Tilburg, Netherlands

21st

Senior race

27:57

7th

Senior team

129 pts

2006

Commonwealth Games

Melbourne, Australia

9th

5000 m

13:40.53

World Cross Country Championships

Fukuoka, Japan

40th

Short race

11:27

14th

Short race team

253 pts

European Cup

Málaga, Spain

2nd

3000 m

8:27.91

European Athletics Championships

Gothenburg, Sweden

2nd

5000 m

13:44.79

European Cross Country Championships

San Giorgio su Legnano, Italy

1st

Senior race

27:56

4th

Senior team

79 pts

2007

European Indoor Championships

Birmingham, United Kingdom

5th

3000 m

8:03.50

World Cross Country Championships

Mombasa, Kenya

11th

Senior race

37:31

8th

Senior team

380 pts

World Championships

Tokyo, Japan

6th

5000 m

13:47.54

World Athletics Final

Stuttgart, Germany

3rd

3000 m

7:49.89

2008

World Indoor Championships

Valencia, Spain

6th

3000 m

7:55.08

European Cup

Annecy, France

1st

5000 m

13:44.07

Olympic Games

Beijing, China

6th (heats)

5000 m

13:50.95

European Cross Country Championships

Brussels, Belgium

2nd

Senior race

30:57

3rd

Senior team

54 pts

2009

European Indoor Championships

Turin, Italy

1st

3000 m

7:40.17 CR

European Team Championships

Leiria, Portugal

1st

5000 m

13:43.01

World Championships

Berlin, Germany

7th

5000 m

13:19.69

European Cross Country Championships

Dublin, Ireland

2nd

Senior race

31:02

2nd

54 pts

Senior team

2010

World Cross Country Championships

Bydgoszcz, Poland

20th

Senior race

34:09

14th

Senior team

230 pts

European Team Championships

Bergen, Norway

1st

5000 m

13:46.93

European Championships

Barcelona, Spain

1st

5000 m

13:31.18

1st

10,000 m

28:24.99

2011

European Indoor Championships

Paris, France

1st

3000 m

7:53.00

World Championships

Daegu, South Korea

1st

5000 m

13:23.36

2nd

10,000 m

27:14.07

2012

World Indoor Championships

Istanbul, Turkey

4th

3000 m

7:41.79

European Championships

Helsinki, Finland

1st

5000 m

13:29.91

Olympic Games

London, United Kingdom

1st

5000 m

13:41.66

1st

10,000 m

27:30.42

2013

European Team Championships

Gateshead, United Kingdom

1st

5000 m

14:10.00

World Championships

Moscow, Russia

1st

5000 m

13:26.98

1st

10,000 m

27:21.71

2014

European Championships

Zürich, Switzerland

1st

5000 m

14:05.82

1st

10,000 m

28:08.11

2015

World Championships

Beijing, China

1st

5000 m

13:50.38

1st

10,000 m

27:01.13

2016

World Half Marathon Championships

Cardiff, United Kingdom

3rd

Individual

59:59

Olympic Games

Rio de Janeiro, Brazil

1st

5000 m

13:03.30

1st

10,000 m

27:05.17

2017

World Championships

London, United Kingdom

1st

10,000 m

26:49.51

2nd

5,000 m

13:33.22

tag: table

text: Circuit wins[edit]

text:
Diamond League
London Grand Prix: 2009 (5000 m), 2011 (3000 m), 2013 (3000 m), 2015 (3000 m)
Herculis: 2011 (5000 m)
Birmingham: 2011 (5000 m), 2012 (2 miles), 2013 (5000 m), 2014 (2 miles), 2016 (3000 m), 2017 (3000 m)
Prefontaine Classic: 2011, 2015, 2016 (10,000 m)
Athletissima: 2015 (5000 m)
Weltklasse Zürich: 2017 (5000 m)
Road
Great South Run: 2009
New York City Half Marathon: 2011
Rock 'n’ Roll Mardi Gras Half Marathon: 2013
Great North Run: 2014, 2015, 2016, 2017
Lisbon Half Marathon: 2015
Cross country
Cross de L'Acier: 2006
Great Edinburgh International Cross Country: 2011

text: Personal bests[edit]

text:
Category

Event

Time

Date

Place

Outdoor

100 m
12.98
2012
Bath

800 m
1:48.69
5 August 2003
Eton

1500 m
3:28.81 AR
19 July 2013
Monaco

One mile
3:56.49
6 August 2005
London

2000 m
5:06.34
9 March 2006
Melbourne

3000 m
7:32.62 NR
5 June 2016
Birmingham

Two miles
8:07.85 AR
24 August 2014
Birmingham

5000 m
12:53.11 NR
22 July 2011
Monaco

10,000 m
26:46.57 AR
3 June 2011
Eugene

Indoor

1500 m
3:39.03
28 January 2012
Glasgow

One mile
3:57.92
4 February 2012
Boston

3000 m
7:33.1 NR
21 February 2015
Birmingham

Two miles
8:03.40 WR
21 February 2015
Birmingham

5000 m
13:09.16[200] AR
18 February 2017
Birmingham

Road

10 km
27:44
31 May 2010
London

15 km
42:03+ AR
26 March 2016
Cardiff

10 miles
46:25
25 October 2009
Portsmouth

20 km
56:27 AR
22 March 2015
Lisbon

Half marathon
59:22a
13 September 2015
Great North Run

59:32 AR
22 March 2015
Lisbon

Marathon
2:06:22 NR
22 April 2018
London Marathon[201]

text: + intermediate split in longer racea = aided road course according to IAAF rule 260.28

text: Biographical works[edit]

text: Autobiography[edit]

text: Twin Ambitions: My Autobiography (2013, Hodder & Stoughton) ISBN 9781444779585

text: Children's fiction[edit]

text: Ready Steady Mo! (with Kes Gray; illustrated by Marta Kissi) (2016, Hodder Children's Books) ISBN 9781444934076

text: Biopic[edit]

text: Mo Farah: No Easy Mile; a non-fictional account of Farah's journey to the Olympics[202]

text: Other[edit]

text: Cardiff native Sonny Double 1 released a biographical grime musical named Mo Farah in 2016.[203]