The present study attempts to improve heat transfer efficiency of a domestic gas burner by enhancing heat transfer from flue gases. Heat transfer can be augmented using the obstacles that are inserted into the flow field near the the heated wall of the domestic gas burner. First, to achieve the maximum efficiency, the insert geometry is optimized by the multi-objective genetic algorithm, so that heat transfer is maximized while minimizing the skin friction. Then, the heating unit is modeled as a three dimensional physical domain. The conservation equations of mass, momentum, energy and species are discretized over the meshing system of control volumes in the domain. The experimental set-up is equally established to measure and validate the numerical results. The effect of the inserts on heat transfer enhancement is studied both numerically and experimentally. The results show that the optimal insert is a triangle with the scaled area of 12.4 mm2. Also, the results indicate that the optimal inserts led to the improvement of heat transfer efficiency by 2.7% compared with the case of similar environment with no insert.

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