多因素影响下的起落架收放系统性能分析

起落架收放系统是集机、电、液的混合复杂系统,影响收放性能的因素也呈多样性.针对目前大多研究并未较好地将收放各部分系统综合考虑的研究现状,提出了一套结合理论分析、多学科仿真技术及试验验证的分析方法,为起落架收放系统提供了较准确的分析手段.首先采用功率键合图法详细地推导了起落架收放系统动力学方程;在理论模型的基础上,建立了结合起落架动力学和液压系统的多学科协同仿真模型,并用试验结果对虚拟样机模型进行验证;最后详细讨论了混合系统中各关键参数对起落架收放性能的影响.研究结果表明,联合仿真模型的压力曲线与试验实测数据吻合良好,同时侧风、摩擦阻力、阻尼孔、液弹、油液泄漏等关键参数对收放性能都有不同程度的影响,分析结果可用于指导起落架收放参数设计、收放故障分析及可靠性研究. 

Retraction system performance analysis of landing gear with the influence of multiple factors

The landing gear retraction system is a mixed complex system consisted of mechanism, electricity and hydraulics. The retraction performance is affected by various factors. In most of the current studies, the subsystems are not well combined. Thus, a set of method combining theoretical analysis, multidisciplinary simulation and test verification was put forward, which provided a more accurate analysis method for the landing gear retraction system. Firstly, the dynamics equations of the retraction system were derived by power bond graph in detail. Then, a multidisciplinary simulation model was established, which combined the mechanism dynamics with the hydraulic system. This virtual prototype was verified by contrasting its results with the test results. At last, the key parameters' influence on the landing gear retraction performance was studied. The results show that, the pressure curves of the co-simulation model agree well with the ones of the test. Meanwhile, some key parameters, including crosswind, friction, damper orifices, liquid capacity and oil leak, affect the landing gear retraction performance in different degrees. Some meaningful results are concluded, which can be used as the guidances of the determination of retraction system parameters, the retraction fault analysis and the reliability study.