Numerical analysis of Secondary flow strength induced by Electrohydrodynamic actuator through a smooth channel

In this paper, the effect of the secondary flow induced by the electrohydrodynamic (EHD) actuator is numerically investigated in the vorticity flux, as a criterion for the secondary flow strength, and the EHD vortices through a smooth channel. In this study, the influence of effectiveness parameters of the EHD as the Reynolds number, applied voltage and the arrangement of the emitting electrode on the vorticity flux, and also relationship between flow and heat transfer characteristics with the vorticity flux are evaluated. The results indicated that in presence of electric field, by increasing the Reynolds number, dimension of the upstream EHD-induced vortices and the vorticity flux are decreased. Also, it is obvious that by increasing the applied voltage, the dimension of the EHD-induced vortices and the vorticity flux are increased. According to numerical results, the heat transfer enhancement is completely depend on the vorticity flux. Also, by changing of the emitter arrangements, the non-dimension average vorticity flux and the average heat transfer enhancement are changed. It is shown that with decrease of the distance between emitter electrode and inlet of channel, from d=50 cm to d=10 cm, the non-dimension average vorticity flux and the average heat transfer enhancement are increased 27.9% and 17.9%, respectively.