在飞机起飞和着陆阶段,气流流经起落架产生的气动噪声是最主要的机体噪声.研究起落架降噪方法对降低飞机的总体噪声具有重要意义.传统的噪声抑制方法(如吹气、吸气、安装整流装置等)通过降低起落架的流动分离,达到抑制噪声的目的,但其结构复杂,且影响到起落架巡航阶段的收回以及平时的维护保养,因此需要寻找新的噪声抑制方法.等离子体激励器非常适合用来控制流动分离,且不存在上述控制方法所带来的起落架维护保养和收回问题.基于此,采用仿真以及实验两种方法,研究了等离子体对圆柱绕流的控制效果.结果表明,等离子体改善了串列圆柱之间的流场分布,降低了远场辐射噪声.等离子体流动控制技术是圆柱绕流流动特性控制的一种有效手段,具有良好的工程应用前景.%A primary component of airframe noises in both takeoff and landing approaches is due to the landing gear.Study on the landing gear noise reduction method is of great significance to reduce the overall noise of aircraft.Conditional noise suppression methods,such as blowing or suction and faring device,could reduce flow separation over landing gear,and the radiated aerodynamic noise is also influenced,but its use is limited by practical considerations like the need to allow easy access for gear maintenance and the ability to stow the gear in cruise,so newly noise suppression methods should be seek.Plasma actuators are ideally suited to flow separation control.For this purpose,based on numerical simulation and aero-acoustic experiment,the plasma's control effect on flow over tandem cylinders was studied.It shows that plasma can improve the tandem cylinder's flow field distribution between the columns and reduce the noise radiation in the far field.Plasma flow control technology is an effective means to control the flow around blunt bodies,and the control method has some practical value in engineering.
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