四参数疲劳定寿方法

对直升机传动系统采用的一种疲劳定寿方法——四参数法进行了研究:首先介绍了四参数应力-循环(S-N)曲线,然后详细介绍了通过材料平均 S-N 曲线获取构件安全 S-N 曲线的步骤以及直升机传动系统四参数疲劳定寿的程序和方法,研究了定寿流程中的各个技术细节.同时介绍了传动系统机匣疲劳试验中的多路协调加载技术以及某传动系统尾减机匣(TGB)的全尺寸疲劳试验情况.最后采用四参数疲劳定寿方法,根据某传动系统尾减机匣全尺寸疲劳试验结果和飞行实测载荷谱,对尾减机匣进行了安全寿命评估.该实例分析表明:四参数疲劳定寿方法为一种有效、可靠的寿命评估方法,具有推广价值. 

Four-parameter life prediction method

Four-parameter life prediction method for helicopter transmission system was studied.Four-parameter stress-number of cycles (S-N) curve was presented first,and then,the derivation of helicopter transmission component safe S-N curve from material mean S-N curve and the scheme for the component life prediction were introduced in detail.Multi-load coordinating loading technology in fatigue test and a tail gear box(TGB) casing full-scale fatigue test were introduced at the same time.Finally,according to the full-scale fatigue test result and flight load survey data,applying the four-parameter life prediction method,the TGB casing life prediction was performed,which indicates that four-parameter life prediction method is a reliable and effective method and is worth to be generalized.