Attenuation of Vibrations in Aircraft Landing Gears due to Impact Loads Using Magnetorheological Dampers

飞机在着陆时会受到冲击载荷的影响。冲击载荷的强度取决于进场速度、着陆条件、操纵面布置、跑道粗糙度等。由此产生的振动可能会影响乘客的舒适性和结构完整性。拟议研究的目的是研究起落架系统通过加入磁流变液阻尼器来降低振动的性能。飞机起落架减振器的基本功能是吸收飞机机身框架在着陆过程中的冲击动能。目前使用的是油气减振器系统，本质上是由气体和油形成流体弹簧和阻尼器的减震器。它们有一个通过流体流动孔口延伸的计量销，可以改变孔口面积。通过对计量销进行整形，使支柱载荷在动态载荷作用下保持相当恒定。如果可以根据负载和进场要求，例如飞机的不同重量或着陆时不同的下沉率，来改变阻尼值，那将是最理想的。

Aircrafts are subject to impact loads during landing. The intensity of the impact loads depends on the approach velocity, landing conditions, control surface deployment, runway roughness etc. The resulting vibrations can affect passenger comfort and structural integrity. The objectives of the proposed research are to study the performance of the landing gear system in reducing vibrations by incorporating magnetorheological fluid dampers. The basic function of the shock absorber in aircraft landing gears is to absorb the impact kinetic energy of the aircraft body frame during landing. Oleo-pneumatic shock absorber system, which are essentially shock absorbers with gas and oil forming a fluid spring and damper, are currently used. They have a metering pin extending through the fluid flow orifice, which can vary the orifice area. By shaping the metering pin the strut load is adjusted to be fairly constant under dynamic loading. It would be ideal if the damping could be varied according to the load and approach requirements such as for different weight of the aircraft or different sink rate at the time of touchdown.