A quad inserted to a turbulent boundary layer of a flat plate and effect on average heat transfer and friction coefficient is studied. To optimize the effect, the edge sizes and distance of the quad from the flat plate is changed to achieve the best enhancement in heat transfer and better reduction in skin friction. For optimization, the genetic algorithm is employed and Pareto curves followed. Flow equations together with SST k-ω turbulence model proved to give reliable solution and stability over 1600 cases under consideration. Governing equations are developed employing TEACH-t algorithm. Based on Pareto front curve, results show that, with no exception over the whole computations, as the heat transfer coefficient rises, skin friction decreases. Three dimensional Pareto curve constructed and results show that, by increasing obstacle cross sectional area, heat transfer coefficient increases as skin friction decreases. The rate of heat transfer enhancement is more sensitive to changes of small geometry modification than for large ones. Since experimental validation for too many cases is impracticable, random comparison between some numerical results and experiments is made, numerical results are in good agreement with experiments.

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