Chapter 5, Problem 5.97EP

3.0 A cold storage is to be maintained at -5°C while the surroundings are at 35°C. The heat leakage from the surroundings into the cold storage is estimated to be 30 kw. The actual C.O.P. of the refrigeration plant used is one third that of an ideal plant working between the same temperatures. Find the power required to drive the plant.

A system produces 10 BTU of work upon addition of 50 kj of heat. Find the heat rejected in ft-lbf.

The following data refers to an air conditioning system to be designed for an industrial process for hot and wet climate. Outside conditions = 38o C DBT and 74 % RH. Required conditions are 23o C DBT and 65 % RH. This is achieved by cooling and dehumidifying and then by heating. If 42 m 3 of air is absorbed by the plant every minute, find the capacity of cooling coil in TR, capacity of heating coil in kW and amount of water removed per hour

CA ges contained in a cylinder is compressed from 1 MPa and 0.05 m² to 2 MPa. Compression is governed by pV4 = constant. Internal energy of gas is given by U = 7.5 pV - 425, kj where p is pressure in kPa and V is volume in m'. Determine heat, work and change in internal energy assuming compression process to be quasistatic. Also find out work interaction, if the 180 kJ of heat is transferred to system between same states. Also explain, why is it different from above.

Water vapor enters a turbine at 6 MPa pressure and 800 ° C temperature and leaves at 20 kPa pressure. Since the heat loss from the turbine with an izanopic efficiency of 95% is 49.7 kJ / kg, a) Find the actual amount of work (kj / kg) produced by the turbine. b) Find the reversible work (kJ / kg) between the inlet and outlet of the turbine. (Take the ambient temperature 20 ° C.)

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A fraction of some power to a motor (1), 2 kW, is turned into heat transfer at 500 K (2) and then it dissipates in the ambient at 300 K (3). Give the rates of exergy along the process 1-2-3.

A compressor compresses the gas in a cylinder at a pressure of 2 Bar, Gas expands from 0.4 m to 0.5 m while pressure is constant. Find the work done of the compressor (a) and Find the sensible heat (b). removed to reduce the temperature of 5 kg of water from 20°C to 5°C, Specific heat capacity is 4.187 kJ/kg K. on Gp

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