7-115 Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.8-m-long t inside which the refrigerant is evaporating at -20°C. Air approaches the tube bank in the normal direction at 0°C and 1 atm with a m velocity of 5 m/s. The tubes are arranged in-line with longitudinal and transverse pitches of SL ST = 1.5 cm. There are 25 rows in t flow direction with 15 tubes in each row. Determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube bank. Evaluate the air properties at an assumed mean temperature of -5°C and 1 atm. Is this a good assumption? 0.8 m Air 0°C 1 atm Sr= 1.5 cm 5 m/s

7-115 Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.8-m-long t inside which the refrigerant is evaporating at -20°C. Air approaches the tube bank in the normal direction at 0°C and 1 atm with a m velocity of 5 m/s. The tubes are arranged in-line with longitudinal and transverse pitches of SL ST = 1.5 cm. There are 25 rows in t flow direction with 15 tubes in each row. Determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube bank. Evaluate the air properties at an assumed mean temperature of -5°C and 1 atm. Is this a good assumption? 0.8 m Air 0°C 1 atm Sr= 1.5 cm 5 m/s

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.4P

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