Question

The mass flow rate in an axial turbine rotor is 100 kg/s and the change in whirl speed is 100 m/s. If the blade speed is 30m/s, then specific work done, given by Euler equation of turbo machine is:

1. the rotor on fluid is 30 MW
2. the rotor on fluid is 3 MW
3. the fluid on rotor is 0.3 MW
4. the rotor on rotor is 30 MW

Answer 1

Correct Answer - Option 3 : the fluid on rotor is 0.3 MW

Concept:

BycEuler equation the specific work done is given by,

W = ṁV_wu

Vw = Change in whirl speed, u = Blade speed

Calculation:

Given:

Vw = 100 m/sec, ṁ = 100 kg/sec, u = 30 m/s

W = ṁVwu

W = 100 × 100 × 30 = 0.3 MW (By the fluid on rotor )