航空液压管路高低周复合疲劳寿命预测研究

Prediction of Fatigue Life for Aviation Hydraulic Pipelines in Combination with High and Low Cycle Loading

为有效预测航空液压管路的疲劳寿命,在分析现有液压管路寿命预测方法不足的基础上,针对飞机液压管路受力特点,分析了液压管路的载荷类型,并对其进行了载荷分解,进而提出了一种基于高低周复合载荷的疲劳寿命预测方法。为验证所提方法的有效性,以某型航空液压管路为例,利用Ansys Workbench软件对其进行仿真分析,在此基础上,对所分析液压管路分别进行了考虑高低周载荷作用和不考虑高低周载荷作用的疲劳寿命预测。对比寿命预测结果发现,高低周复合疲劳载荷对液压管路的寿命影响较大,在预测液压管路的疲劳寿命时,需同时考虑高周疲劳载荷和低周疲劳载荷的作用。

In order to predict the fatigue life of aviation hydraulic pipelines reliably,on the basis of existing fatigue life prediction methods being insufficiency for hydraulic pipelines and in view of the stress characteristics of aircraft hydraulic pipelines,the types of loads acting on hydraulic pipelines are analyzed and their loads are decomposed,a fatigue life prediction method is proposed for the hydraulic pipeline under combined high and low cycle loading.Subsequently,a simulation analysis is performed on a specific type of aircraft hydraulic pipeline by using the Ansys Workbench to validate the effectiveness of the proposed method.Based on this analysis,fatigue life predictions are made in consideration of both high and low cycle loads,and under no consideration of the effects of high and low cycle loads.The results show that the effect of combined high and low cycle fatigue loads has a significant influence on the fatigue life of hydraulic pipeline.When the fatigue life of hydraulic pipelines is subjected to the prediction,it is necessary to consider the effects of both high cycle fatigue loads and low cycle fatigue loads simultaneously.