Forced air at T∞ = 25°C and V = 12 m/s is used to cool electronic elements on a circuit board. One such element is a chip, 4 mm × 4 mm, located 153 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 Nu_x=0.04Re_x^{0.85}\Pr^{\frac{1}{3}}Nux=0.04Rex0.85Pr31 Estimate the surface temperature of the chip if it is dissipating 32 mW.

Forced air at T∞ = 25°C and V = 12 m/s is used to cool electronic elements on a circuit board. One such element is a chip, 4 mm × 4 mm, located 153 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 Nu_x=0.04Re_x^{0.85}\Pr^{\frac{1}{3}}Nux=0.04Rex0.85Pr31 Estimate the surface temperature of the chip if it is dissipating 32 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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.31P

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