Experimental investigation on the vectoring spray based on a novel synthetic jet actuator

Abstract

In order to realize large-area and high-temperature plate heat dissipation in a restricted space, an innovative vectoring spray cooling device based on a novel synthetic jet actuator is proposed. Depending on the different response characteristics of different piezoelectric diaphragms to the same electric signals, this device doesn't need transmission or rotating parts, but is able to change its spray impingement direction. It effectively saves installation space and improves the spray cooling efficiency. The research shows that the visualized spray vectoring angle is basically consistent with the vectoring angle based on its potential-core momentum, which indicated that the distribution of spray particles is closely related to the velocity field of synthetic jets. Both of them can be used as effective methods to evaluate the spray vectoring characteristic. Using the Coanda effect can amplify the spray vectoring deflection angle from 10° to 16°, and the enhancement effect reaches more than 60% in this paper. The greater the thickness differences of the diaphragms, the better the vectoring characteristic of the spray. The maximum vectoring deflection angle from −25° to 24° is realized in this paper. However, the heat dissipation capacity depends on the vectoring spray velocity. The use of a diaphragm combination with a greater difference in thickness results in a greater loss of velocity with the variation of driving frequency. Finally, the vectoring angle based on its potential-core momentum is also basically consistent with the vectoring angle based on its temperature field, which indicates that the spray vectoring angle can be directly controlled to accurately remove the high temperature point or district.