Engineering, 07.04.2020 01:05 xkxd13x

An array of electronic chips is mounted within a sealedrectangular enclosure, and colling is implemented by attaching analuminum heat sink (k=180 W/mK). The base of the heat sinkhas dimensions of w1=w2=100mm, while the 6 fins are of thicknesst=10mm and pitch S=18mm. The fin length is Lf=50 mm, and thebase of the heat sink has a thickness of Lb=10mm.
If cooling is implemented by water flow through the heat sink, with u[infinity]=3 m/s and T[infinity]=17 C, what is the base temperatureTb of the heat sink when the power dissipation by the chips isPelec=1800W? The average convection coefficient for surfacesof the fins and the exposed base may be estimated by assumingparallel flow over a flat plate. Properties of the water maybe approximated as k=0.62 W/mK, Î½=7.73E-7 m2/s, andPr=5.2.

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An array of electronic chips is mounted within a sealedrectangular enclosure, and colling is impleme...

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