瞬态冲击载荷作用下舵板结构的疲劳寿命预测

通过开展材料性能试验与分析,获取材料的循环应力-应变曲线,采用不同方法对Manson-Coffin公式中的疲劳常数进行估算,对R≠–1的应变-寿命曲线进行修正.运用雨流计数法计算得到结构的载荷谱,采用Neuber近似解法求出舵板结构的局部应力应变.分别应用道林公式和兰德格拉夫公式2种方法计算结构的累计损伤效应,并对2种方法的计算结果进行对比分析.提出采用应变能等效原则开展试件的疲劳寿命试验方法,试验结果与仿真计算结果较为近似.

Fatigue life predication of rudder structure under transient shock load

The cyclic stress-strain curve of a certain material was acquired by material property experiment andanalys-is. The fatigue constants in the Manson-Coffin equation were estimated with varies methods, and the strain-life curve while R≠–1 was corrected. The load spectrum on the structure was calculated with rain-flow counting method, and the local stress-strain on the rudder structure was calculated by Neuber approximate way. Dowling formula and Landgraf formula were used separately to calculate the structure damage cumulative, and the results were comparatively analysed. At last, the fatigue life experiment method was put forward based on strain energy equivalent principle. The research shows that the calculation data coincides with the test data well.