A liquid enters a 2.5-cm-diameter tube with a length of 5.0 m. The liquid inlet temperature is 20°C and the tube wall temperature is 60°C. Average liquid properties are Cp = 2.0 kJ /kg·K, μ = 10 mPa·s, and r = 900 kg/m3. At a flow rate of 1200 kg/h, the liquid outlet temperature is measured to be 30°C. a) Estimate the liquid outlet temperature when the flow rate is reduced to 400 kg/h. b) What is the thermal resistance for convection inside the pipe? (Answer 38.3°C)

A liquid enters a 2.5-cm-diameter tube with a length of 5.0 m. The liquid inlet temperature is 20°C and the tube wall temperature is 60°C. Average liquid properties are Cp = 2.0 kJ /kg·K, μ = 10 mPa·s, and r = 900 kg/m3. At a flow rate of 1200 kg/h, the liquid outlet temperature is measured to be 30°C. a) Estimate the liquid outlet temperature when the flow rate is reduced to 400 kg/h. b) What is the thermal resistance for convection inside the pipe? (Answer 38.3°C)

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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