GATE 2022 ME: RAC, PPE & IC Engines Quiz - 3

A refrigerator working on Bell Coleman Cycle operates between pressure limits of 1 bar and 9 bar. The air standard COP is

A refrigerator is working on Bell Coleman Cycle with air as working fluid. The pressure ratio is changed from 4 to 8 . The percentage change in COP is

Consider a refrigeration system working an reversed brayton cycle. Air enters the compressor at 100 kPa, 17°C and compressed to 400 kPa. Air is then cooled to 20°C before it enters the turbine for a mass flow rate of 2 kg/s, the net power input (in kW) is (Take =1.4)

Air is compressed in a compressor with isentropic efficiency 85%. The inlet and outlet temperature of air is 300 k and 430 k respectively. The theoretical temperature at the outlet of compressor will be (in K)

Which of the following statements are correct with respect to gas refrigeration cycle.

(a) They have low refrigeration capacity

(b) They involve simple and lighter component

(c) They are suitable for air craft cooling

(d) All of above

In reciprocating compressor, clearance is provided

(a) To improve the volumetric efficiency of the compressor.

(b) To accommodate valves

(c) To account for thermal expansion due to temperature variation

(d) To reduce power consumption of compressor