Thermodynamics: An Engineering Approach
9th Edition
ISBN: 9781259822674
Author: Yunus A. Cengel Dr., Michael A. Boles
Publisher: McGraw-Hill Education
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Chapter 8.8, Problem 67P
Refrigerant-22 absorbs heat from a cooled space at 50°F as it flows through an evaporator of a refrigeration system. R-22 enters the evaporator at 10°F at a rate of 0.08 lbm/s with a quality of 0.3 and leaves as a saturated vapor at the same pressure. Determine (a) the rate of cooling provided, in Btu/h, (b) the rate of exergy destruction in the evaporator, and (c) the second-law efficiency of the evaporator. Take T0 = 77°F. The properties of R-22 at the inlet and exit of the evaporator are: h1 = 107.5 Btu/lbm, s1 = 0.2851 Btu/lbm·R, h2 = 172.1 Btu/lbm, s2 = 0.4225 Btu/lbm·R.
FIGURE P8–67E
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Chapter 8 Solutions
Thermodynamics: An Engineering Approach
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