Question

A steam turbine has an inlet of 3 kg/s water at 1200 kPa, 350 °C and velocity 15 m/s. The exit is at 100 kPa, 150 °C and very low velocity. Find the specific work and power produced?

Answer 1

Answer:

W = 377.312 KJ/kg

P =1131.937 KW

Explanation:

$\dot m = 3 kg/s$

V_1 =15m/s

P_1 = 1200kPa

T_1 = 350 DEGREE C

For above value , and from super heated tables H_1 = 3153.3 Kj/kg

P_2 = 100kPa

T_2 = 150 degree C

For above value , and from super heated tables H_2 = 2776.1 Kj/kg

v_2 = 0

from energy equation

$Q + H_1 +\frac{v_1^2}{2} = W + H_2 +\frac{v_2^2}{2}$

$H_1 +\frac{v_1^2}{2} = W + H_2$       { V_2 = 0, Q =0}

$3153.3 + \frac{15^2}{2} = 2776.1 +W$

W = 377.312 KJ/kg

power is given as

$P = \dot m * w$

P = 3*377.312 = 1131.937 KW