(8) A refrigerant 12 refrigeration system requires a load of 54 kW at an evaporator pressure of 270 kPa and a condenser pressure of 1009 kPa. The refrigerant is subcooled 10 degrees before entering the expansion valve and vapor is superheated 14 degrees before entering the compressor. A twin-cylinder compressor with stroke equal to 1.25 times the bore is to be used at a speed of 27 r/s. The volumetric efficiency is 84 per cent. Determine (a) the quantity of cooling water in the condenser for an 11-degree increase in temperature, (b) the bore and stroke, and (c) the compressor power. Ans. (a) 1.40 kg/s, (b) 8.58 x 10.73 cm, (c) 10.5 kW

(8) A refrigerant 12 refrigeration system requires a load of 54 kW at an evaporator pressure of 270 kPa and a condenser pressure of 1009 kPa. The refrigerant is subcooled 10 degrees before entering the expansion valve and vapor is superheated 14 degrees before entering the compressor. A twin-cylinder compressor with stroke equal to 1.25 times the bore is to be used at a speed of 27 r/s. The volumetric efficiency is 84 per cent. Determine (a) the quantity of cooling water in the condenser for an 11-degree increase in temperature, (b) the bore and stroke, and (c) the compressor power. Ans. (a) 1.40 kg/s, (b) 8.58 x 10.73 cm, (c) 10.5 kW

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter22: Condensers

Section: Chapter Questions

Problem 7RQ: When a standard-efficiency air-cooled condenser is used, the condensing refrigerant will normally be...

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Show your complete solution.
A refrigerant 12 refrigeration system requires a load of 54 kW at an evaporator pressure of 270 kPa and a condenser pressure of 1009 kPa. The refrigerant is subcooled 10 degrees before entering the expansion valve and vapor is superheated 14 degrees before entering the compressor A twin-cylinder compressor with stroke equal to 1.25 times the bore is to be used at a speed of 27 r/s The volumetric efficiency is 84 per cent. Determine (a) the quantity of cooling water in the condenser for an 11-degree increase in temperature, (b) the bore and stroke, and (c) the compressor power. Ans (a) 1.40 kg/s, (b) 8.58 x 10.73 cm, (e) 10.5 kW
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Show your complete solution.
The evaporator and condenser temperature of a 20 to-ton -capacity freezer are -28 OC and 23 OC respectively .The refrigerant 22 is subcooled by 3 OC before it enters the expansion valve and is superheated to 8 OC before leaving the evaporator .The compression is isentropic . A six cylinder single acting with stroke equal to bore running at 250 rpm is used . Neglect valve throttling and clearance effect detemine refrigerant effect calculate the theoretical piston displacement heat removed through the condenser calculate the theoretical bore and stroke of the compressor
The evaporator and condenser temperature of a 20 to-ton -capacity freezer are -28 OC and 23 OC respectively .The refrigerant 22 is subcooled by 3 OC before it enters the expansion valve and is superheated to 8 OC before leaving the evaporator .The compression is isentropic . A six cylinder single acting with stroke equal to bore running at 250 rpm is used . Neglect valve throttling and clearance effect Determine the refrigerating effect Calculate the theoretical piston displacement .Calculate the heat removed though the condenser Calculate the theoretical bore and stroke of the compressor
1. A Freon-12 refrigerator producing a cooling effect of 20 kJ/s operates on a simple cycle with pressure limits of 1.509 bar and 9.607 bar. The vapour leaves the evaporator dry saturated and there is no undercooling. Determine the power required by the machine. If the compressor operates at 300 rpm. and has a clearance volume of 3% of stroke volume, determine the piston displacement of the compressor. For compressor assume that the expansion following the law pv13 = constant.
Need solution through half hr please