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Find the specific reversible work for a steam turbine with inlet at 4 MPa, 500°C and an actual exit state of 100 kPa, x = 1.0 with a 25°C ambient temperature.

Find the specific reversible work for a steam turbine with inlet at 4 MPa, 500°C and an actual exit state of 100 kPa, x = 1.0 with a 25°C ambient temperature. Correct Answer 850.0 kJ/kg

To = 25°C = 298.15 K, hi = 3445.2 kJ/kg; si = 7.090 kJ/kg K, he = 2675.5 kJ/kg; se = 7.3593 kJ/kg K w(rev) = (hi – Tosi) – (he – Tose) = (hi – he) + To(se – si) = (3445.2 – 2675.5) + 298.2(7.3593 – 7.0900) = 769.7 + 80.3 = 850.0 kJ/kg.

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