Control of boundary layer by ionic wind for heat transfer

In this study, local convection heat transfer technology was investigated using ionic wind. The characteristics of ionic wind using wire and plate electrodes are studied by experiment and numerical method. A particle image velocimetry (PIV) test was conducted in a wind tunnel to observe the flow behavior by the ionic wind on the heated surface. A new boundary layer was formed on the heated surface which was controlled by the ionic wind, regardless of the Reynolds number of bulk flow. The surface averaged heat transfer coefficient with the ionic wind increased by 11% at low Reynolds number (100–200) and decreased by 19% at high Reynolds number (2500–3500). It was also found that the zigzag type of wire arrangement enhanced the heat transfer coefficient by 40% compared with the single wire. It is thus concluded that ionic wind can be used for enhancing the convection heat transfer rate or insulating the local surface according to its operating condition.