起落架缓冲器阻尼孔特性分析

当飞机着陆下沉速度较快时,油-气式缓冲器因快速压缩会引起缓冲器内部压力剧增和阻尼孔处产生射流现象。为减小缓冲器内部压力和油液流经阻尼孔的流速,以油液入口速度、阻尼孔的孔长、孔径和倒直角为研究对象,通过单因素法对各因素变化引起的缓冲器内压力和流速的变化特性进行分析。通过Fluent软件进行仿真计算,结果表明:油液入口速度越大,缓冲器内部压力和油液流速也越大;孔长对缓冲器内部压力影响较小,对阻尼孔中油液流速影响较大;随孔径减小,缓冲器内压力和阻尼孔中油液流速不断增大;倒直角对缓冲器内压力影响较小,但可降低阻尼孔中的油液流速。研究结果可为缓冲器的优化设计提供参考。

Analysis on the Characteristics of the Damping Hole of Landing Gear Buffer

When the landing speed of the aircraft is fast,the rapid compression of the oil gas buffer will cause the pressure surge inside the buffer and efflux phenomenon at the damping hole.In order to reduce the pressure inside the buffer and the flow velocity of oil through the damping hole, taking the oil inlet velocity, the hole length, the hole diameter and the chamfer of the damping hole as the research object, the variation characteristics of the pressure and flow velocity in the buffer caused by the changes of various factors were analyzed by using the single factor method. Simulation calculation was carried out by using Fluent software. The results show that the greater the inlet velocity of oil is, the greater the pressure inside the buffer and the flow velocity are. The hole length has little influence on the pressure inside the buffer and more influence on the flow velocity of the oil in the damping hole; with the decrease of the hole diameter, the pressure inside the buffer and the flow velocity of the oil in the damping hole increase continuously;the chamfer has little influence on the pressure inside the buffer, but it is useful for reducing the flow velocity of the oil in the damping hole. The research results can provide reference for the optimal design of buffer.