Aj. Fowler et A. Bejan, CORRELATION OF OPTIMAL SIZES OF BODIES WITH EXTERNAL FORCED-CONVECTION HEAT-TRANSFER, International communications in heat and mass transfer, 21(1), 1994, pp. 17-27
This paper shows how to correlate the optimal sizes of bodies with spe
cified external forced convection heat transfer, when the objective is
to minimize 1) the total rate of entropy generation, or 2) the total
cost. Specific results are reported for the cylinder in cross-flow, th
e sphere, and the flat plate in parallel flow. The results are present
ed in terms of dimensionless parameters that show that regardless of t
he body shape, the optimal size increases monotonically with the heat
transfer duty parameter. A universal correlation is obtained by nondim
ensionalizing the body size as a Reynolds number based on the transver
sal length scale of the flow, and by replacing the body with an equiva
lent one in two-dimensional flow. The optimal sizes correlated in this
manner can be applied to bodies of other shapes.