航空发动机轴承腔中油滴运动与沉积的特性分析  

Analysis of the Oil Droplet Motion and Deposition Characteristics in an Aeroengine Bearing Chamber

作　　者：王军[1] 陈国定[1] 刘亚军[1] 

机构地区：[1]西北工业大学机电学院,陕西西安710072

出　　处：《摩擦学学报》2010年第4期361-366,共6页Tribology

基　　金：国家自然科学基金项目(50975233)的资助

摘　　要：本文在获得轴承腔中气相介质流场的基础上,采用Lagrangian方法建立油滴在气相介质流场中运动的分析模型,通过瞬时步进法数值模拟油滴的运动过程,获得了油滴直径和旋转轴转速对油滴运动过程中的速度和轨迹影响的规律.基于获得的油滴与腔壁碰撞前的运动状态,以及结合油滴与腔壁的碰撞模型,实现了油滴直径和旋转轴转速对碰撞后油滴沉积率和动量转移率影响规律的分析.结果表明:油滴直径和旋转轴转速对油滴速度及轨迹,以及油滴沉积率及动量转移率都有很大影响,而且前者的影响更为明显.与国外同等条件下的试验结果对比表明,本文提出的油滴运动与沉积特性分析方法具有较好的可靠性和精度.碰撞前后油滴运动状态和沉积率及动量转移率的计算,为下一步油膜厚度和速度的计算,继而为轴承腔润滑设计和换热分析提供了初始条件.The forms of lubrication medium include film,droplet and gas in an aeroengine bearing chamber,in which the wall film flow characteristics has the most important effect on the heat transfer characteristics of the wall.The oil film thickness and velocity were related to the droplet motion and deposition characteristics.The study of the droplet motion and deposition characteristics is the fundamental for lubrication design and heat analysis in an aeroengine bearing chamber.Based on the gas flow field in the bearing chamber,the Lagrangian method was used to establish analytical model of droplet motion.The numerical simulation of droplet motion was achieved by an instantaneous step method.The effects of droplet diameter and rotor speed on droplet velocity and trajectory were obtained.Based on the droplet motion state and droplet-wall impact model,the analysis of the effects of droplet diameter and rotor speed on droplet deposition efficiency and momentum transfer efficiency was achieved.The results indicated droplet diameter and rotor speed had great effect on droplet velocity,trajectory,deposition efficiency and momentum transfer efficiency,especially for the former.The analytical method in this paper had high reliability and precision by contrasting computational result with experimental result.The computation of droplet motion state,deposition efficiency and momentum transfer efficiency supplied initial condition to the computation of the oil film thickness,velocity,lubrication design and heat analysis of an aeroengine bearing chamber.

关 键 词：轴承腔 油滴轨迹 两相流 沉积率 动量转移率 

分 类 号：TP183[自动化与计算机技术—控制理论与控制工程]