Chapter 7, Problem 7.30P

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 air conditioner in a house or a car has a cooler that brings atmospheric air from 30 degree Celsius to 10 degree Celsius, both state at 101 kPa. For a flow rate of 0.75 kg/s find the rate of heat transfer

A factory generates compressed air from 100 kPa, 17°C by compression to 800 kPa, 500 K, after which it cools in a constant pressure cooler to 300 K, (see Fig. P4.36). Find the specific compressor work and the specific heat transfer in the cooler. 1 2 3 Compressor -w. Compressor section Cooler section

A mixing chamber with heat transfer receives 2 kg / s of R - 134a at 1 MPa, 50 ° C in one line and 1 kg / s of R - 134a at 15 ° C, quality 40% in a line with a valve. The outgoing Now is at 1 MPa, 70 ° C Find the rate of heat transfer to the mixing chamber

· A closed gaseous system undergoes a reversible process with constant pressure of 200kpa. 2500 kJ of heat is rejected, and the volume changes from 5m3 to 2m3. Find the change in internal energy

(15%) A small expander (a turbine with heat transfer) has 0.05 kg/s helium entering at 1000 kPa, 550 K and leaving at 250 kPa, 300 K. The power output on the shaft measures 55 kW. Find the rate of heat transfer, neglecting kinetic energies.

THERMODYNAMICS A certain gas expand from 7ft3 to 23ft3 while the pressure remains constant at 17.5psia. Find the work nonflow in the system in BTU.

A cycle HE does 60kJ of work per cycle. If the efficiency of the heat engine is 60%. The heat rejected per cycle is.

Air is heated at constant pressure from 2 7 degrees C to 57 degrees C at 3 bar in a heater from an infinite heat source at temperature 227 degrees C Find the gain in availability of air and the effectiveness of the heater. Assume To = 280K and Cp =1.0 kj/kgK.