考虑热弹流的齿轮多学科设计优化

Multidisciplinary Design Optimization of Gear Considering Thermo-Elastic-Hydrodynamic

现有航空发动机齿轮优化设计时通常不考虑尺寸变化对齿轮局部温度梯度的影响,导致应力计算结果与实际相差较大,优化效果不好。为此,提出了基于热弹流分析的齿轮多学科设计优化方法,首先通过热弹流润滑理论对齿轮进行热弹流数值分析,计算出油膜厚度、压力等参数,然后通过求解能量方程得到齿轮温度分布,采用该温度进行应力计算,最终在优化过程中考虑了结构、传热、强度的相互影响,提高了优化结果的准确性。将此方法应用于某传动系统行星齿轮优化设计,该方法与传统设计方法相比,能提高行星齿轮设计能力,优化后行星齿轮减重10.2%。

In the optimization of aeroengine gears,the influence of gear size change on the local temperature gradient is usually not considered,resulting in a large difference between the stress calculation results and the actual results,and the effect of optimization is not good.Therefore,a Multidisciplinary Design Optimization(MDO) method for gears based on Thermal-Elastic-Hydrodynamic(TEHD) analysis is proposed.Firstly,the lubrication theory of TEHD is used to analyze the gears,and the parameters of oil film thickness and pressure are calculated.Then,the temperature distribution of gears is obtained by solving the energy equation,and the stress is calculated by using this temperature.Finally,the structure,heat transfer and strength are considered in the optimization process and the accuracy of optimization results is improved by considering the interaction of disciplines.This method is applied to the optimal design of planetary gears in a transmission system.The results show that this method can improve the design ability of planetary gears and reduce the weight of planetary gears by 10.2% compared to the traditional design method.