叶片径向变形的动态概率分析方法

Dynamic probabilistic analysis for turbine blade radial deformation

为了有效地进行高压涡轮叶片设计和优化,提高叶尖径向运行间隙设计和控制的合理性,本文考虑了材料属性和边界条件的非线性、载荷的动态性、变量的随机性,在确定性分析的基础上对叶片径向变形进行了动态概率分析。首先,介绍了高效率动态概率分析的极值响应面法(Extremum Response Surface Method,ERSM)及其数学模型;其次,将该方法应用到叶片径向变形的动态概率分析中,得出了各输入输出随机变量的分布特征及影响叶片径向动态变形的主要因素,即燃气温度和转子转速;最后,通过对三种方法进行比较。结果表明:ERSM的计算精度与MonteCarlo法基本保持一致,比传统响应面法稍高;其计算时间为Monte Carlo法的1/66、为传统响应面法的1/3。以此验证了该方法在叶片径向变形动态概率分析方面的可行性和有效性,为叶片径向变形的优化设计和叶尖径向运行间隙设计提供了参考。

In order to effectively design and optimize High Pressure Turbine(HPT) blade and Blade-Tip Radial Running Clearance(BTRRC),by fully considering the nonlinearity of material and boundary conditions,the dynamic loads and the randomness of variables,the dynamic probalistic analysis of blade radial deformation is implemented based on the deterministic analysis.Firstly,the Extremum Response Surface Method(ERSM) with high efficiency and the mathematical model of ERSM are introduced.Then the ERSM is applied in the dynamic probalistic analysis of blade radial deformation and the distribution characteristics of input-output variables and the important factors(gas temperature and rotate speed) are gained.Through the comparsion of methods in the dynamic probabilistic analysis of blade radial deformation,the results obtained show that the computational accuracy of ERSM is consistent with that of Monte Carlo Method(MCM) and is slightly better than that of Response Surfance Method(RSM),the computational time of ERSM is 1/66 to that of MCM and 1/3 to that of RSM,respectively.The feasibility and validity of ERSM in the dynamic probabilistic analysis of blade radial deformation is demonstrated and a promising reference can be provided for the optimization design of blade radial deformation and the probabiliatic analysis of BTRRC.