THERMODYNAMICS (LL)-W/ACCESS >CUSTOM<
9th Edition
ISBN: 9781266657610
Author: CENGEL
Publisher: MCG CUSTOM
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Chapter 11.10, Problem 80P
An ideal gas refrigeration system with two stages of compression with intercooling as shown in Fig. P11–80 operates with air entering the first compressor at 90 kPa and −24°C. Each compression stage has a pressure ratio of 3, and the two intercoolers can cool the air to 5°C. Calculate the coefficient of performance of this system and the rate at which air must be circulated through this system to service a 45,000 kJ/h cooling load. Use constant specific heats at room temperature.
FIGURE P11–80
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A 100 x 300 mm ammonia compressor with a compression efficiency of 82% operates with a suction pressure of 291.57 kPa and a condenser pressure of 1203.7 kPa at 30 rps. The refrigerant cools 100 kg/min of water from 250C to 20C and assuming 5% of the useful refrigerating effect is lost due to the process of cooling, give that,
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Chapter 11 Solutions
THERMODYNAMICS (LL)-W/ACCESS >CUSTOM<
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