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对电磁力控制下的翼型绕流和升力的初始响应过程和变化规律进行了实验和数值研究.实验和计算中,均采用示踪粒子方法,使流场可视化.引进边界涡通量的概念,推导了电磁力与边界涡通量以及升力的定量关系,根据边界涡通量的分布,对绕流流场对升力的影响进行了分析,初步揭示了翼型绕流电磁控制的机理.结果表明,未加电磁力时,翼型绕流和升力呈周期性变化.在流向电磁力作用下,翼面上的旋涡消失点以一定的规律向后缘移动,最终以涡对的形式脱离翼面,流场也因此趋于定常.电磁力可以改变流场,提高流场的负边界涡通量的强度,有利于升力的提高.但同时电磁力也使翼面压力增加,使升力下降.由于使升力提高的因素起主要作用,故上翼面的流向电磁力可提高升力,且电磁力愈大,升力提高愈多.覆盖在上翼面局部位置的电磁力也能抑制流动分离和提高升力,电磁力作用于后部效果更好.
The initial response process and the change law of airfoil flow and lift under electromagnetic force control are studied experimentally and numerically.The tracer particle method is used in experiment and calculation to visualize the flow field.The concept of introducing boundary vortex flux The relationship between the electromagnetic force and the boundary vortex flux and the lift force is deduced. According to the distribution of the boundary vortex flux, the influence of the flow field on the lift force is analyzed, and the mechanism of electromagnetic control of the airfoil flow is revealed. Results The results show that the airfoil flows periodically and the lift changes cyclically without electromagnetic force.With the flow of electromagnetic force, the vanishing point of the vortex on the airfoil moves to the trailing edge with a certain regularity, Therefore, the flow field tends to be steady. Electromagnetic force can change the flow field and improve the strength of the negative boundary vortex flux in the flow field, which is propitious to the improvement of lift force, but at the same time, the electromagnetic force also increases the pressure of the airfoil to decrease the lift force. So that the factors that enhance the lift play a major role, so the flow of electromagnetic force on the upper airfoil can improve the lift, and the greater the electromagnetic force, the more the lift to enhance the coverage of the upper airfoil local electromagnetic force can also inhibit flow separation and improve lift, Electricity Force is applied to the back of better.