OPTIMAL SIZING OF PLANAR THERMAL SPREADERS

Two-dimensional cylindrical and three-dimensional Cartesian thermal sp readers are studied. One of the surfaces is convectively coupled to a uniform environmental temperature while the opposite surface is subjec ted to a uniform heat flux distribution over a portion of its boundary . The problem is generalized through the introduction of appropriate d imensionless variables, and analytical solutions for the temperature f ield are presented for each coordinate system. The solutions depend on the usual geometric and heat transfer groups. It is found that, for a range of realist Biot numbers and a given ratio of the spreader to he ater dimensions, a dimensionless spreader thickness exists for which t he temperature of the heater reaches a minimum value. Optimal thicknes s curves are presented for these ranges.