The condenser of a steam power plant operates at a pressure of 7.38 kPa (Tsat = 40°C). Steam at this pressure condenses on the outer surfaces of horizontal pipes through which cooling water circulates. The outer diameter of the pipes is 3 cm, and the outer surfaces of the pipes are maintained at 30°C. Determine the rate of condensation of steam per unit length of a horizontal pipe. The properties of water at the saturation temperature of 40°C are: hfg = 2407 × 10^3J/kg and ρv=0.05 kg/m3. The properties of liquid water at the film temperature: ρl = 994 kg/m3, Cpl =4178 J/kg°C, µl = 0.72 × 10^-3 kg/m.s, kl = 0.623 W/m°C Select one: a. 0.0026 kg/s b. 0.0046 kg/s c. 0.0016 kg/s d. 0.0036 kg/s

The condenser of a steam power plant operates at a pressure of 7.38 kPa (Tsat = 40°C). Steam at this pressure condenses on the outer surfaces of horizontal pipes through which cooling water circulates. The outer diameter of the pipes is 3 cm, and the outer surfaces of the pipes are maintained at 30°C. Determine the rate of condensation of steam per unit length of a horizontal pipe. The properties of water at the saturation temperature of 40°C are: hfg = 2407 × 10^3J/kg and ρv=0.05 kg/m3. The properties of liquid water at the film temperature: ρl = 994 kg/m3, Cpl =4178 J/kg°C, µl = 0.72 × 10^-3 kg/m.s, kl = 0.623 W/m°C Select one: a. 0.0026 kg/s b. 0.0046 kg/s c. 0.0016 kg/s d. 0.0036 kg/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.

Chapter9: Heat Transfer With Phase Change

Section: Chapter Questions

Problem 9.21P

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