solve, show assumptions and full solutions 1. Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of0.8-cm-outer-diameter and 0.4-m-long tubes 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 meanvelocity of 4 m/s. The tubes are arranged in-line with longitudinal and transverse pitches ofS₁ =ST=1.5 cm. There are 30 rows in the flow direction with 15 tubes in each row.a. Determine the refrigeration capacity of the system.b. Determine the pressure drop across the tube bank.0°C1 atm4 m/s0.4 mAirST=1.5 cm0.8 cmS₁ = 1.5 cmRefrigerant, -20°C

The refrigeration capacity of the system is 7285 W.The pressure drop across the tube bank is 391.6…

Answered: 1. Air is to be cooled in the…

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.65P

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One house owner with a pond on his property has decided to use the pond water to cool his house. His idea is to flow air through a thin smooth 10-cm-diameter copper tube that could be submerged into the pond. The water in the pond, at few meters below the surface is typically maintained at a constant temperature of 15°C. If he assumes the air (~1 atm) entering the copper tube at a mean temperature of 30°C with an average velocity of 2.5 m/s, determine the necessary copper tube length that would be needed so that the outlet mean temperature of the air is 20°C. You may consider the convection heat transfer coefficient of 1000 W/m2·K on the outer surface of the copper tube, between the pond water and copper tube. Since the copper tube is thin, the conduction resistance of the tube wall may be neglected.
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