Homework Answers

In an ideal Rankine Cycle, steam at 5 MPa and 500 o C enters the turbine and after expansion

exits as saturated vapor. For 110,000 kg/hr of sream, find: a) Ideal power output of the Turbine

(kW), b) Power to drive the pump (kW), c) Rate of Heat Added (kW), d) thermal efficiency of

cycle and engine, e) steam rate of the cycle and engine, f) Heat Rate

7. Wet steam at 200 o C and 20 % moisture is compressed in an irreversible adiabatic

process to a pressure of 2.5 MPa and 250 o C. Determine: a) actual work of

compression, b) compression efficiency, c) irreversibility, d) internal reheat.

6. Steam expands isentropically from 2 MPa and 375 o C to a final temperature of 95 o C.

Find the final quality and the work for a non-flow and steady flow processes.

5. There are 3 kg/min of steam undergoing an isothermal process from 30 bar and 350 o C

to 7 bar. (note 1 bar = 100 kPaa). Find: a) ΔS (kJ/k), b) Heat transferred (kJ), c) ΔH

(kJ), d) ΔU (kJ)

4. To what temperature must a rigid tank containing dry and saturated steam at 130 o C be

cooled to yield a mixture of 25 % quality.

3. A 2-kg steam water mixture at 1.0 MPaa is contained in an inflexible tank. Heat is

added until the pressure rises to 3.5 MPaa and the temperature to 400 o C. Determine:

a) Heat transferred (kJ), b) ΔH (kJ), c)ΔS (kJ/k)