A 65% efficient turbine receives 2 m^3/s of water from a reservoir. The reservoir water surface is 45 m above the centerline of the turbine. The water leaves the turbine through a 1-m diameter pipe into a river. How many kilowatts of power is generated by the turbine? Assume losses in the flow system to be 5 m.

Respuesta :

Answer:

[tex]P_{out} = 508.071 kW[/tex]

Given:

efficiency of the turbine, [tex]\eta [/tex] = 65% = 0.65

available gross head,  [tex]H_{G}[/tex] = 45 m

head loss,  [tex]H_{loss}[/tex] = 5 m

Discharge, Q =  [tex]2 m^{3}[/tex]

Solution:

The nozzle is 100% (say)

Available power at the inlet of the turbine,  [tex]P_{inlet}[/tex] is given by:

[tex]P_{inlet} = \rho Qg(H_{G} - H_{loss})[/tex]                  (1)

where

[tex]\rho [/tex] = density of water = 997 [tex]kg/m^{3}[/tex]

acceleration due to gravity, g = [tex]9.8 m^{2}[/tex]

Using eqn (1):

[tex]P_{inlet} = 997\times 2\times 9.8(45 - 5) = 781.65 kW[/tex]

Also, efficency, [tex]\eta [/tex] is given by:

[tex]\eta = \frac{P_{out}}{P_{inlet}}[/tex]

[tex]0.65 = \frac{P_{out}}{781.648\times 1000}[/tex]

[tex]P_{out} = 0.65\times 781.648\times 1000 = 508071 W = 508.071 kW[/tex]

[tex]P_{out} = 508.071 kW[/tex]