变壁厚气冷涡轮叶片结构参数化设计方法

叶片叶身截面内腔型线的光滑过渡是航空发动机变壁厚涡轮叶片结构设计的关键.为解决变壁厚插值在最大壁厚点处出现拐点而导致过渡不光滑的问题,提出变壁厚叶片结构设计方法即变壁厚抛物线插值法.该方法基于管道相交投影线拟合中弧线法,利用壁厚系数及其对应关系控制壁厚,实现变壁厚涡轮叶片结构参数化设计.设计实例结果表明:应用变壁厚抛物线插值法对不同壁厚气冷涡轮叶片进行结构设计,叶身截面内腔型线光滑,在最大壁厚点处不会出现拐点过渡.

Parametric design method of air-cooled turbine blade structure with variable thickness

Smooth transition of blade body inner cavity curve is critical to structure design of aeroengine turbine blades with variableathickness. In order to solve the problem of appearing inflection point in the biggest wall thickness causing the not smooth transition withinvariable thickness interpolation,design method (variable thickness parabolic interpolation method)of blades structure with variablethickness was put forward. The method based on the fitting curve method of projecting curves through pipe intersection,utilizing coefficientof wall thickness and corresponding relationship between wall thickness,realizing parametric design of turbine blades with variablethickness. Results of design instance show that using variable thickness parabolic interpolation method to design air-cooled turbine bladestructure with variable thickness,blade body inner section curves is smooth that not presenting transition of inflection point in the point ofthe biggest wall thickness.