不同叶片尾缘结构对流换热特性实验

Experiment on convective coefficient of different turbine blade trailing edges

关键词:  涡轮叶片  叶片尾缘  气膜冷却  对流换热系数

Key words:  Turbine blade  Trailing edge  Film cooling  Convection coefficient

摘要:

为了研究不同叶片尾缘结构对对流换热系数的影响规律,设计了三种尾缘结构,并搭建了实验台,采用红外热像仪对叶片尾缘的壁温进行测量。研究结果表明,(1)三种尾缘结构的对流换热系数沿壁面的分布有很大差异,针对实验件I,对流换热系数存在一最大值,且最大值出现的位置随着吹风比的增加而逐渐远离气膜出口；(2)实验件II和III的对流换热系数沿壁面均呈现逐渐降低的趋势,但降低的规律二者又不相同；(3)在相同壁面位置,实验件III的对流换热系数最高,而实验件I的对流换热系数最低,因此可以认为,实验件III所示的尾缘结构更有利于对叶片尾缘更好的冷却。

Abstract:

In order to study the film convection coefficient of blade trailing edge, three kinds of trailing edges were designed, and the experimental system was built. The convection coefficient of trail edges was studied by the experimental method with infrared cameras. The experimental results show that there is a large difference for the film convection coefficient of three kinds of trailing edges, and there is a largest convection coefficient value for the test piece I, and the situation of the largest value on the surface of trailing edge is moved with the change of the blowing ratio. The convection coefficient of test piece II and III are all gradually decreased alone the surface of trailing edge. At the same situation on the surface of trailing edge, the convection coefficient of test piece III is higher than the other test pieces, so the configuration of test piece III is suitable for the design of turbine blade trailing edge. 