In an experiment, a metallic cylinder internally by an electric heater and subjected to a cross flow of air. The velocity and temperature of the air were V = 12 m/s and To = 26.2°C, respectively. The heater power dissipation was measured to be P = 48 W, and the surface temperature was maintained at T= 128.4°C. Neglect heat loss by radiation and conduction. (a) Determine the convection heat transfer coefficient from the experimental observation. in (b) Compare the experimental result with the convection coefficient computed from Zhukauskas relation. Assume, for air at T = 300 K: v= 15.89x10° m²/s, k= 26.3x10* W/m.K, Pr= 0.707; for air at T, = 401 K: Pr= 0.690. %3D %3! Show all calculations.

In an experiment, a metallic cylinder internally by an electric heater and subjected to a cross flow of air. The velocity and temperature of the air were V = 12 m/s and To = 26.2°C, respectively. The heater power dissipation was measured to be P = 48 W, and the surface temperature was maintained at T= 128.4°C. Neglect heat loss by radiation and conduction. (a) Determine the convection heat transfer coefficient from the experimental observation. in (b) Compare the experimental result with the convection coefficient computed from Zhukauskas relation. Assume, for air at T = 300 K: v= 15.89x10° m²/s, k= 26.3x10* W/m.K, Pr= 0.707; for air at T, = 401 K: Pr= 0.690. %3D %3! Show all calculations.

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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