涡轮动叶顶部换热的萘升华模拟实验研究

Experimental research of heat transfer on the tip of turbine rotor using naphthalene sublimation technique

为了研究叶顶形状对涡轮动叶顶部上换热特性的影响,在低速涡轮实验台上采用萘升华技术对2种叶顶(平叶顶和凹槽叶顶)的换热系数进行了实验测量。同时为增加实验的可信性,将该测试方法在吹风平板上进行了验证。实验结果表明:萘升华法可以较准确地获得平板上的换热趋势,可以用于测量涡轮叶顶壁面的换热特性;采用凹槽结构将影响叶顶的泄露流动,从而改变叶顶局部区域的换热分布。实验测量结果能为涡轮动叶顶部换热的研究提供一定的参考。

To investigate the effect of a blade tip structure on heat transfer characteristics at a gas turbine rotor tip,the heat transfer coefficients on two kinds of the blade tip（flat tip and squealer tip）were measured in a low speed rotating turbine experimental set-up using naphthalene sublimation technique.The test method was verified on the blowing plate to increase the experimental reliability.The experimental results show that the naphthalene sublimation method can accurately obtain the trend of heat transfer on the plate,and can be used to measure the local heat transfer characteristics on the tip of rotating turbine.The squealer structure affects the tip leakage flow,so the distribution of heat transfer on the tip will change.The test results can provide the reference value for the research of the heat transfer at the rotor tip.