In a steam power plant operating on a ideal Rankine cycle, superheated steam enters the turbine at 3 MPa and 350 C. The condenser pressure is 75 kPa. The thermal efficiency of the cycle is ________%. Given data: For saturated liquid, at p = 75 kPa, hf = 384.39 kJ/kg, vf = 0.001037 m3/kg, sf = 1.213 kJ/kgK. At 75 kPa, hfg = 2278.6 kJ/kg, sfg = 6.2434 kJ/kgK At P = 3 MPa and T = 350 C (superheated steam), h = 3115.3 kJ/kg, s = 6.7428 kJ/kgK.

In a steam power plant operating on a ideal Rankine cycle, superheated

1.	In a steam power plant operating on a ideal Rankine cycle, superheated steam enters the turbine at 3 MPa and 350 C. The condenser pressure is 75 kPa. The thermal efficiency of the cycle is ________%. Given data: For saturated liquid, at p = 75 kPa, hf = 384.39 kJ/kg, v_f = 0.001037 m³/kg, s_f = 1.213 kJ/kgK. At 75 kPa, h_fg = 2278.6 kJ/kg, s_fg = 6.2434 kJ/kgK At P = 3 MPa and T = 350 C (superheated steam), h = 3115.3 kJ/kg, s = 6.7428 kJ/kgK.
A.	0.26 or 26%
B.	0.25 or 25%
C.	0.27 or 27%
D.	0.36 or 36%
Answer» B. 0.25 or 25%

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