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作用。冲击载荷的强度取决于进场速度、着陆条件、操纵面展开、跑道粗糙度等。由此产生的振动会影响乘客舒适度和结构完整性。本研究的目的是探讨磁流变阻尼器对起落架系统减振性能的影响。飞机起落架中减震器的基本功能是吸收着陆时飞机机体框架的冲击动能。目前使用的是油-气动减震器系统，其本质上是具有形成流体弹簧和阻尼器的气体和油的减震器。它们具有延伸穿过流体流动孔口的计量销，这可以改变孔口面积。通过使计量销成形，支柱载荷被调节为在动态载荷下相当恒定。如果阻尼可以根据载荷和进场要求而变化，例如对于不同的飞机重量或着陆时不同的下沉率，则将是理想的。

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.