An electronic device is to be cooled by natural convection in atmospheric air at 20?C. The device generates internally 50 W and only one of its external surfaces is suitable for attaching fins. The surface available for attaching cooling fins is 0.15 m tall and 0.4 m wide. The maximum length of a fin perpendicular to the surface is limited to 0.02 m and the temperature at the base of the fin is not to exceed 70?C in one design and 100?C in another.Design an array of fins spaced at a distance (s) from each other so that the boundary layers will not interfere will each other appreciable and maximum rate of heat dissipation is approached. For the evaluation of this spacing, assume that the fins are at a uniform temperature. Then select a thickness (t) that will provide good fin efficiency and ascertain which base temperature is feasible.GIVENAn electronic device with vertical aluminum fins in airAir temperature (T??) = 20?CHeat generation (qG) = 50 WHeight of surface (H) = 0.15 mWidth of surface (w) = 0.4 mMaximum fin length (Lf) = 0.02 mMaximum base temperatures: Tb1 = 70?CTb2 = 100?CFin spacing = sFin thickness = tASSUMPTIONSThe fins are at a uniform temperature equal to the basetemperature

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L<0,02 m н- 0,15 m w-0.4 m н t=?