Engineering, 10.12.2019 01:31 babysitterwick

Consider a square chip of width wc = 25 mm. the chip is cooled using a dielectric liquid with t[infinity] = 25o c and h = 1,500w/m2k. the heat sink is fabricated from copper (k = 400 w/mk). its base has negligible heat resistance and the contact resistance between the sink and the chip is also negligible. the width of each fin cannot be smaller than 1 mm. the height of the fins, hf, due to space constraints cannot exceed 6 mm. also, the spacing between fins cannot be smaller than 1 mm, so that flow through the fins can be sustained at a sufficient rate so that the convective heat transfer coefficient can be maintained at the value stated. find the optimum number of fins needed to maximize the heat dissipated while minimizing the mass of the fins (which is proportional to its cost) by optimizing the spacing between the fhs. notice that the surface of the chips cannot exceed t = 85 c

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Consider a square chip of width wc = 25 mm. the chip is cooled using a dielectric liquid with t[infi...