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前轮摆振是飞机地面动力学中的重点研究课题。基于多体动力学理论,采用有限元方法及点线吻合的方法处理缓冲器的柔性问题,建立了前起落架全柔性体摆振动力学模型,并采用起落架静力试验的结果对模型进行校验;给出了以飞机速度和防摆阻尼系数组成的飞机摆振稳定区域图;研究了轮胎的侧向刚度与转动间隙对临界防摆阻尼的影响。结果表明:采用点线吻合方法能准确有效地模拟柔性缓冲器的运动特性;采用二次防摆阻尼在速度高于10 m/s情况下,临界防摆阻尼随速度的增大逐渐减小甚至为零;随轮胎侧向刚度的增长而增加,转动间隙会显著提高所需的临界防摆阻尼。
The front wheel shimmy is a key research topic in ground dynamics of aircraft. Based on the multi-body dynamics theory, the finite element method and the line-line fitting method are used to deal with the problem of the buffer’s flexibility. The full flexible body oscillating vibration model of the nose landing gear is established, and the model is calibrated using the results of the landing gear static test The plane map of the stability of the aircraft is given, which is composed of the aircraft speed and anti-roll damping coefficient. The influence of the lateral stiffness of the tire and the rolling clearance on the damping of the critical anti-slippage is studied. The results show that the method of point-line fitting can accurately and effectively simulate the dynamic characteristics of the flexible bumper. With the second anti-sway damping at a speed higher than 10 m / s, the critical anti-sway damping decreases with the increase of the speed and even decreases Is zero; as the lateral stiffness of the tire increases, turning clearance significantly increases the required critical anti-slippage damping.