Question

Question 1

a) Determine the specific enthalpy of steam at 15 bar and 275°C .

b) Determine the degree of superheat and entropy of steam at 10 bar and 380 °C.

c) A superheated steam at 12.5 MN/m2 is at 650°C .Determine its specific volume.

Question 2

A superheated steam at 24 bar and 500 °C expands at constant volume until the pressure becomes 6 bar and the dryness fraction is 0.9. Calculate the changes in the internal energy of steam. Sketch the process in the form of a P-v diagram.

Question 3

Steam at 10 bar and 200 °C enters a convergent-divergent nozzle with a velocity of 60 m/s and leaves at 1.5 bar and with a velocity of 650 m/s. Assuming that there is no heat loss, determine the quality of steam leaving the nozzle.

Question 4

The temperature of feed water entering a boiler is 311 °C and steam is produced at 40 bar and 500 °C. The rate of heat transfer to the surroundings is 35 kW. Determine the mass flow rate of the working fluid for a heat input to the boiler of 6 MW.

Question 5

Exhaust steam from a turbine enters a condenser with a specific enthalpy of 2164 kJ/kg and a velocity of 75 m/s. During the cooling process, the heat loss to the cooling water per kg of working fluid is 1680 kJ/kg. The condensate exits the system with a velocity of 12 m/s. Sketch a systems diagram for the condenser and determine the specific enthalpy of the working fluid at exit from the condenser.

Question 6

A steady flow boiler is supplied with water at 15 kg/s, 100 bar pressure, and 200 °C. The water is heated and turned into steam. The steam leaves at 100 bar and 500 °C. Determine the heat transfer rate.  

Answer 1

With the time constraint we have, I was able to solve all, except for question 4. Hope it's helpful.