A motor body is 350 mm in diameter (outside) and 300 mm long. Its surface temperature should not exceed X/4 ℃ (where X=Reg. No), when dissipating 400W. Longitudinal fins of 15 mm thickness and 40 mm height are proposed. The convection coefficient is 35 W/m2 ℃. Atmospheric temperature is 30℃. Thermal conductivity = 40 W/m℃. Determine (i) Number of Fins required (ii) Heat transfer rate from the fin (ii

A motor body is 350 mm in diameter (outside) and 300 mm long. Its surface temperature should not exceed X/4 ℃ (where X=Reg. No), when dissipating 400W. Longitudinal fins of 15 mm thickness and 40 mm height are proposed. The convection coefficient is 35 W/m2 ℃. Atmospheric temperature is 30℃. Thermal conductivity = 40 W/m℃. Determine (i) Number of Fins required (ii) Heat transfer rate from the fin (ii

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.39P

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