By passing an electric current through the foil, heat is dissipated uniformly within the foil and the corresponding flux (P elec) may be inferred from related voltage and current measurements. Consider conditions for which To = Tb = 25°C, Pelec = 2000 W/m2, L = 7 mm, and k = 0.05 W/m.K. (1) With water flow over the surface, the foil temperature measurement yields Ts = 30°C. Determine the convection heat transfer coefficient for both cases below. The foil has an emissivity of 0.15 and is exposed to large surroundings at 25°C. (2) On the other hand, if air flows over the surface and the temperature measurement yields Ts 120°C, how the convection heat transfer coefficient will be different?

By passing an electric current through the foil, heat is dissipated uniformly within the foil and the corresponding flux (P elec) may be inferred from related voltage and current measurements. Consider conditions for which To = Tb = 25°C, Pelec = 2000 W/m2, L = 7 mm, and k = 0.05 W/m.K. (1) With water flow over the surface, the foil temperature measurement yields Ts = 30°C. Determine the convection heat transfer coefficient for both cases below. The foil has an emissivity of 0.15 and is exposed to large surroundings at 25°C. (2) On the other hand, if air flows over the surface and the temperature measurement yields Ts 120°C, how the convection heat transfer coefficient will be different?

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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