To increase the rate of heat transfer from a device, which has 0.1 m² of exposed surface, you added 500 pin fins of 4 cm length and 2 mm diameter on top of the device's exposed surface. How much (i.e., by what factor) did the rate of total heat transfer rate (from the surface) increase? Assume that the convection coefficient is 42 W/m².K, and the thermal conductivity of the fin material is 240 W/m-K. Neglect radiation.

To increase the rate of heat transfer from a device, which has 0.1 m² of exposed surface, you added 500 pin fins of 4 cm length and 2 mm diameter on top of the device's exposed surface. How much (i.e., by what factor) did the rate of total heat transfer rate (from the surface) increase? Assume that the convection coefficient is 42 W/m².K, and the thermal conductivity of the fin material is 240 W/m-K. Neglect radiation.

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 8.13P

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