航空发动机涡轮叶片径向变形的概率分析

摘要

To describe the changing rule of turbine blade radial deformation during aeroengine operation, and improve reasonality of blade-tip clearance design and control, the probabilistic analysis of blade radial deformation was analyzed based on finite element and response surface method considering many random variables. Through thermal and structural analysis under the typical loads, the changing rules of blade deformation with time were calculated, as well as the maximal deformation points were regarded as the probabilistic analysis points. With the effect of thernal loads and mechanical loads, it was available to calculate the distribution probabilistic and allowable reliability of blade radial deformation, and sensitivity analysis of random variables influencing blade radial deformation were completed by fusing respond surface and Monte Carlo method. The results show that blade radial radial deformation and safy deformation probabilistic basicly meets the design requierment, the main factors influening bald radial deformation are temperature, speed and quality.%为描述航空发动机涡轮叶片径向位移的变化规律,改善叶尖间隙设计和控制的合理性,考虑多种随机变量,融合有限元和响应面方法进行了叶片径向变形的概率分析。通过对涡轮叶片在典型载荷下的热分析和结构分析,计算出叶片变形随时间的变化规律,并找出最大位移点作为概率分析的计算点;在计算点处考虑热载荷和离心载荷作用,结合响应面拟合蒙特卡洛法计算出了危险点处的叶片径向变形的分布概率和符合设计要求的可靠度,并分析了影响间隙量的随机因素的灵敏度。结果表明：叶片径向变形量和安全变形概率基本符合设计要求;影响叶片径向位移变化的主要因素是温度、转速和质量。