双转子轴间滑油颗粒运动轨迹参数化模型

Parametric Model of Lubricant Particle Trajectory inAnnulus Inter-Spools

关键词:  航空发动机  参数模型  转子  润滑  流场  质点运动学  离散相模型  颗粒运动轨迹

Key words:  Aeroengine  Parameter model  Rotor  Lubrication  Flow field  Particle kinematics  Discrete phase model  Particle motion trajectory

摘要:

为研究双转子轴间滑油颗粒运动对环下润滑收油效率及轴承腔油气分离效率的影响，建立了对转轴间在边界层流场结构下基于质点运动学的滑油颗粒运动轨迹参数化模型，并采用经实验验证的计算流体力学（CFD）数值计算结果进行验证。双转子轴间的边界层流场结构的确定运用了对湍流边界层卡门三层结构速度分布进行修正的方法。结果表明：给出的参数化模型可以很好地描述双转子轴间的滑油颗粒运动规律。直径较大的颗粒径直或沿弧线迅速到达外轴，而直径较小的颗粒中存在一个在给定停留时间内使颗粒无法到达外轴的最大直径，小于这一临界直径的颗粒在有轴向气流时将被吹离轴间环腔。

Abstract:

In order to study the effects of lubricant particle movement in the annulus inter-spools on oil collection efficiency of under-ring lubrication and oil-gas separation efficiency in bearing chamber, a lubricant particle trajectory parametric model was established based on particle kinematics under the boundary layer flow field structure in the annulus inter-spools, and the numerical results of computational fluid dynamics (CFD) verified by experiments were used to verify the model. The boundary layer flow field structure was determined by modifying the velocity distribution of Karman three-layer structure in turbulent boundary layer.The results show that the proposed parametric model can well describe the particle motion law in the annulus inter-spools. The larger particles reach the outer axis directly or along the arc line, and the smaller diameter particles have a maximum diameter that make particles can not reach the outer axis in a given residence time. The particles smaller than this critical diameter will be blown away from the annulus when there is an axial flow.