Numerical Simulation and Optimization of Heat Transfer in Reciprocating Flows

Heat transfer in a laminar reciprocating flow in a two-dimensional channel based on the Womersley number, Prandtl number, and pressure gradient amplitude is numerically simulated using the spectral element method. It was shown that in high Womersley number flows the temperature distribution is highly affected by the Richardson annular effect. Although increasing of the Richardson annular effect enhances the heat transfer rate, it simultaneously the reduces flow penetration length and as a result total amount of transferred heat. These two contradictory effects cause the presence of an optimum frequency to reach a maximum heat transfer rate. In the present study, the pressure gradient amplitude has been chosen as a design parameter rather than penetration length and optimum values of frequency and geometrical parameters are investigated.