Chapter 8, Problem 8.52P

4. An evaporator has R-410A at -20°C and quality 80% flowing in. The exit flow is saturated vapor at -20°C. a. Consider the heating to be a reversible process and find the specific heat transfer from the entropy balance. (Answer: 48.7 kJ/kg) b. If the heat source was at -10°C and the inlet and outlet streams still have the same properties as in a), calculate the specific entropy generation? (Answer: 7.33 J/(kg K))

4. Air at a temperature of 500 0C is compressed at a constant pressure of 1.2MPa from a volume of 2 m3 to a volume of 0.4m3 . If the initial internal energy decrease is 4820 KJ, find a. The work done during the reversible compression b. The heat transferred c. The change of enthalpy d. The average specific heat at constant pressure

3. An adiabatic compressor takes argon from 100 kPa, 300 K to 2000 kPa. The compressor efficiency is 80%. (a) Find the outlet temperature (K) and the work (kJ/kg) (b) Find the entropy generation (kJ/kg-K)

Please be very detailed

The pressure and temperature entering the turbine is 1800kpaa and 380oC. The temperature leaving the turbine is 20kpa. The quality of steams entering the condenser is 90%. Find the turbine work in kJ/kg.

A Factory uses a vapor absorption refrigerator to cool its products, the heat is supplied to generator by steam at 150 C (hfg=2500kJ/kg) and 90% dry. The temperature of the evaporator is to be maintained at -5 C. the refrigeration capacity is 20 Tonnes and actual COP is 70% of the maximum, atmospheric Pressure is 1 bar and ambient temperature 30 C. find the maximum COP. mass of steam per hour

An isentropic turbine process 5kg/s of steam at 4MPa, which is exhausted at 50kPa and 100 C. Five percent pf this flow is diverted for feedwater heating at 700kPa. Find the power produced by the turbine.

Steam to a turbine at a mass flow rate of 1.4 kg/s, 700 kPa pressure and 400 °C enters the temperature. Steam at 100 kPa pressure and 1.4 m3/kg specific volume exits the turbine. Heat transfer from turbine to environment 50 kW, with turbine Since the boundary temperature between the environment is 70 °C, a) Find the power produced by the turbine, entropy produced in the turbine and isentropic efficiency of the turbine. Note: The changes in kinetic and potential energies will be neglected and T (K) = 273 + °C will be taken.

The turbine section in a jet engine receives gas (assume air) at 1200 K, 800 kPa with an ambient atmosphere at 80 kPa. The turbine is followed by a nozzle open to the atmosphere and all the turbine work drives a compressor receiving air at 85 kPa, 270 K with the same flow rate. Find the turbine exit pressure P₂ so the nozzle has an exit velocity of 800 m/s.