A finned-tube heat exchanger is used as an air-conditioning condenser. During a steady state operation, refrigerant in the tubes remains 2-phase state throughout the heat exchanger at the condensing temperature 67 °C. Air enters the condenser at inlet temperature 22 °C and air mass flow rate is 0.7 kg/s. Refrigerant-side convection thermal resistance and tube wall conduction resistances are negligible. Airside total surface area is 8 m² and overall surface efficiency is 0.75. Airside average convection coefficient is 102 W/(m²K). The specific heat of air is 1,006 J/(kgK). Determine the heat transfer rate in W.

A finned-tube heat exchanger is used as an air-conditioning condenser. During a steady state operation, refrigerant in the tubes remains 2-phase state throughout the heat exchanger at the condensing temperature 67 °C. Air enters the condenser at inlet temperature 22 °C and air mass flow rate is 0.7 kg/s. Refrigerant-side convection thermal resistance and tube wall conduction resistances are negligible. Airside total surface area is 8 m² and overall surface efficiency is 0.75. Airside average convection coefficient is 102 W/(m²K). The specific heat of air is 1,006 J/(kgK). Determine the heat transfer rate in W.

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 7.46P

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