射流振荡器的回流特性和切换特性研究

射流振荡器是一种能在入口提供定常流动,出口产生非定常脉动射流的流体器件。本文以数值模拟为主要手段,研究一种射流振荡器内部流场特征,并研究其回流特性和切换机理。提出主射流沿着其中一个出口流出,由于受到腔体低压区的作用,另一个出口产生回流。回流程度随进出口压力和环境温度的升高而减小,随劈距的增加而增大。随控制端流量的增加,出口相对入口流量不断减小,继续增加控制端流量,射流发生切换。对射流振荡器的研究设计具有一定的参照意义。

Research on the Reverse Flow and Switching Characteristics of Fluidic Oscillators

Fluidic oscillator is a device which can generate unsteady flow at the outlet, when supplied with steady flow at the inlet. In this paper, numerical simulation is used to research the internal flow field characteristics of a fluidic oscillator, as well as the reverse flow characteristics and switching mechanism. The main jet flows along one of the outlet, and the reverse flow is generated in another outlet due to the effect of the low pressure area of the cavity. The reflux degree decreases with the increasing of the pressure ratio and ambient temperature, and increases with the increasing of the splitting distance. The flow rate ratio between inlet and outlet decreases with the increasing of control flow , and then the jet is switched when continue to increase the control flow. And the results presented in the paper can be applied to some significance for the study of fluidic oscillators design.