合成射流激励器对射流矢量的影响

Jet vectoring using synthetic jet actuators

关键词:  射流技术  激励器  流动分布  向量  数值仿真

Key words:  Fluidics  Exciter  Flow distribution  Vector  Numerical simulation

摘要:

合成射流激励器全流场计算模型—X L模型,实现了将激励器腔体及外部受控流场作为单连域的计算处理。对合成射流激励器在不同工作状态下控制宏观低速流流动进行了数值分析和机理探讨。结果显示:应用合成射流激励器可以有效控制宏观低速流流动方向,通过改变激励器的工作参数和布置位置可以控制主流的偏转角度;激励器处于"拉"模式对主流的控制效果更明显,且激励器与受控主流之间存在一个最佳距离,使得对主流的矢量控制效果最大;合成激励器工作形成的漩涡对强度受合成射流频率和速度幅值影响。压强梯度的存在和旋涡的卷吸作用是合成射流激励器控制宏观低速流流动方向的主要因素。

Abstract:

X-L model, a whole flow-field computing model for synthetic jet actuator, which considers the actuator cavity, the exit throat, and the external flow field as a single computational region. Based on this computing model, numerical computations were performed for a low speed primary jet vectored using different synthetic jet actuators.It is shown that the synthetic jet actuators can control the vector of a low speed primary jet effectively and the primary jet direction can be controlled by altering the working parameters and locations of actuators. When the actuator is operated in the "pull" mode, the primary jet is vectored larger comparable to that of "push" mode, and there must be an optimal distance between the actuator exit and the primary jet, for which the largest vectoring benefit can be obtained. The frequency and velocity amplitude of the synthetic jet affect the strength of the vortex.The formation of "low pressure closed circumfluence region" and the entrainment of vortexes are the main reasons for vectoring a low speed jet.