Engineering, 05.05.2020 22:12 brookesquibbs

Forced air at 25C and 10m/s is used to cool chips on a circuit board. Consider a chip, 4mm x 4mm, located 120mm from the leading edge of the board. An empirical correlation has been established for the local Nusselt number:

Nu_x = 0.04 * Re_x^0.85 * Pr^(1/3)

Estimate the surface temperature of the chip if it is dissipating 30mW.

(Thermophysical properties of air at 25C are needed to solve this problem. Please state your reference source for this information.)

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Forced air at 25C and 10m/s is used to cool chips on a circuit board. Consider a chip, 4mm x 4mm, lo...

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