A long, cylindrical, electrical heating element of diameter D = 14 mm, thermal conductivity k = 251 W/m - K, density p = 2,805 kg/m3, and specific heat cp = 903 J/kg · K is installed in a duct for which air moves in cross flow over the heater at a temperature and velocity of 30°C and 9 m/s, respectively. (a) Neglecting radiation, estimate the steady-state surface temperature when, per unit length of the heater, electrical energy is being dissipated at a rate of 1,033 W/m.

A long, cylindrical, electrical heating element of diameter D = 14 mm, thermal conductivity k = 251 W/m - K, density p = 2,805 kg/m3, and specific heat cp = 903 J/kg · K is installed in a duct for which air moves in cross flow over the heater at a temperature and velocity of 30°C and 9 m/s, respectively. (a) Neglecting radiation, estimate the steady-state surface temperature when, per unit length of the heater, electrical energy is being dissipated at a rate of 1,033 W/m.

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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.36P

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