Forced air at Too = 25°C and V = 17 m/s is used to cool electronic elements on a circuit board. One such element is a chip, 4 mm x 4 mm, located 129 mm from the leading edge of the board. Experiments have revealed that flow over the board is disturbed by the elements and that convection heat transfer is correlated by an expression of the form Nuz = 0.04RE0.85 Pr3 V, T Chip Board L mm Estimate the surface temperature of the chip if it is dissipating 38 mW.

Forced air at Too = 25°C and V = 17 m/s is used to cool electronic elements on a circuit board. One such element is a chip, 4 mm x 4 mm, located 129 mm from the leading edge of the board. Experiments have revealed that flow over the board is disturbed by the elements and that convection heat transfer is correlated by an expression of the form Nuz = 0.04RE0.85 Pr3 V, T Chip Board L mm Estimate the surface temperature of the chip if it is dissipating 38 mW.

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 7.22P

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