基于CFD内流耦合仿真的燃油柱塞泵滑靴副动态润滑特性研究

Research on Dynamic Lubrication Characteristics ofSlipper Pair in Aviation Fuel Piston Pump Based onCFD Internal Flow Coupling Simulation

关键词:  燃油柱塞泵  滑靴副  润滑模型  动态润滑特性

Key words:  Fuel piston pump  Slipper pair  Lubrication model  Dynamic lubrication characteristics

摘要:

针对航空燃油柱塞泵滑靴副自适应油膜的动态润滑问题，基于牛顿拉夫逊方法，建立了考虑滑靴副油膜支承作用与其动力学状态动态耦合关系的滑靴副润滑计算模型。在此基础上，计入前级部件内流作用对油膜特性的影响，通过CFD内流分析和Reynolds润滑模型相结合的仿真方法，对航空柱塞泵滑靴副及其前级部件进行了一体式联合仿真研究。研究结果表明：仿真与试验结果的误差保持在4.3%以内，CFD仿真方法可以实现对滑靴副前级部件内流场的准确模拟；转速从4kr/min增至5kr/min时，膜厚的最大倾覆值减小至原数值的27.15%，并且低压区滑靴厚度变化率的增大率最大可达62.02%；而出口压力增大率为66.7%时，引起全周期内膜厚变化率波动幅度不同程度的增大；在转动周期内，滑靴的自适应润滑效果通过油膜厚度场和压力场的耦合变化形成自适应动压支承效应来实现。

Abstract:

To solve the dynamic lubrication problem of adaptive fuel film inside slipper pair of aero-engine fuel piston pump, a calculation model of slipper pair overturning was established. The model was based on Newton-Laphson algorithm, which in consideration of the coupling relationship between film hydrodynamic bearing and dynamic state of slipper. On this basis, the integrated simulation study on slipper pair and the front parts of a certain aviation piston pump was developed. Considering the influence of the flow inside the front part on the oil film characteristics, a simulation method combining CFD internal flow analysis with Reynolds lubrication model was used in the study. The simulation results show that the CFD simulation results agree with the experimental results, and the error is 4.3%. When the rotational speed increases from 4kr/min to 5kr/min, the maximum overturning value of film thickness decreases to 27.15% of the original value, and the maximum increase rate of the thickness change rate in the low pressure region reaches 62.02%. When the increase rate of outlet pressure is 66.7%, the fluctuation amplitude of film thickness change rate in the whole cycle increased to varying degrees. In the rotation period, the slipper achieve adaptive lubrication effect through the coupling change of film thickness and pressure field, which cause an adaptive dynamic pressure bearing.