In this paper, by combining the Computational Fluid Dynamics (CFD) and NSGA II algorithm, the forced convective heat transfer ow in a stack of horizontal parallel plates has been multi-objectively optimized. In the optimization process, the distance between the plates in the set of parallel channels has been changed so as to simultaneously optimize the amount of heat transfer between the plates and uid and the pressure drop of the uid (maximization of heat transfer and minimization of pressure drop). The Pareto front, which illustrates the changes of heat transfer from the plates and the pressure drop of uid, simultaneously, has been presented in the results section. This result contains important information regarding the thermal designing of stack of channels subjected to forced convective heat transfer. The Pareto front has been obtained for four di erent uids that have di erent Prandtl (Pr) numbers (mercury, air, water, and oil), and the results related to each uid have been discussed. Finally, the multi-objective optimization results obtained in this paper have been compared with the results of the asymptotic analysis method (which is a single-objective method aimed at increasing the amount of heat transfer from plates) for internal uid ows, and useful information has been obtained.
