航空发动机载荷谱计算方法研究

关于雨流计数法判别准则，不同文献给出的表达式并不统一，对不同的表达式进行了分析，建立了与应力应变迟滞循环理论相符的“三线法”雨流计数判别式。结合航空发动机飞行数据特点，利用3σ准则剔除伪数据，利用特定程序剔除“连续等值中间点”，获取了正确的峰谷序列。由于雨流计数中“二次调整”载荷次序时机的不同，存在两种载荷谱计算方法，并利用实例和试飞数据进行了对比分析，得出了两种计算方法都能够获得正确的载荷谱结果。最后通过计算分析获得了多个飞参发参载荷谱小循环剔除阀值，避免了统一固定阀值对有用循环数据的盲目剔除。计算方法和结论为后续载荷谱统计奠定了重要基础，也为其他结构载荷谱计算提供了参考。

Research on Load Spectrum Calculation Method for Aircraft Engine

There are different mathematic expressions in different papers on rain-flow counting criterion, which were deep analyzed in the paper. Based on above three-segment rule , which was corresponding with the stress-strain hysteresis loop theory. Considering to flight data characteristic of aircraft engine cor-rect peak-valley sequences could be extracted by using 3σ criterion aiming to deleting wrong data firstly and by using special program which could delete continuous equivalent data points. Because of different adjustment occasion in two times adjustment method for load sequences there were two calculation ways. The conclusion was drawn that two calculation ways both extracted correct load spectrum and the results were quite no differences through analyzing both results of example and flight data. Finally the deleting threshold values for deleting small value cycle of some flight and engine parameters were obtained through analyzing different results,which avoided blind deleting available data with constant threshold value. The calculation and results established important foundations,and provided reference to load spectrum of other structures.