Multi criteria optimization of conjugate convection in a rectangular duct

A "holistic" approach is utilized to "thermally" optimize a system of convecting duct, on the basis of the two symbiotic physical parameters influencing the thermal performance with different modes of convection outside and turbulent forced convection inside the duct. The two physical quantities viz heat transfer per unit mass and the entropy generated by the system are simultaneously considered to arrive at an optimum. Correlations are developed for the heat transfer and the entropy generated by the system taken as the performance parameters as mentioned above. From these, the individual optima are obtained, and these are synergistically considered by the use of a composite objective function based on the penalty involved in deviation from the optima to design the system. Thus, by way of this, a "holistic" optimum is arrived at.