短周期风洞叶栅端壁换热试验研究

Heat Transfer Experiment of End-wall in Short Duration Wind Tunnel

实验对短周期风洞中无气膜孔和带气膜孔时涡轮叶片端壁的换热做了实验研究,得出了无气膜孔端壁换热系数和叶栅入口雷诺数、出口马赫数之间的变化关系。另外得出了带气膜孔端壁在不同的叶栅入口雷诺数、出口马赫数、流量比时对换热系数的影响。实验结果表明:无气膜孔端壁上的换热系数分别在不同的叶栅入口雷诺数和出口马赫数下有着明显的变化;带气膜孔端壁上换热系数随流量比和叶栅入口雷诺数的增大而增大,而在低流量比时马赫数对端壁换热系数没有明显的影响。

The heat transfer at the end-wall with holes, as well as the one without them, of a turbine blade are researched experimentally in the short duration wind tunnel. The relationship amongst the heat transfer coefficient of the end-wall without holes., the Reynolds number at the inlet of leading edge of the turbine blade, and the Mach numbers at the outlet are determined. The influence of inlet Reynolds number, outlet Mach number and flow ratio respectively on the heat transfer coefficient at the end-wall with holes are also determined. The experiment results show that： first, the coefficient of the end-wall without holes varies obviously as the inlet Reynolds number or the outlet Mach number varies ; second, the coefficient of the end-wall with holes increases as either the flow rate or the outlet Mach number increases, which would not be affected at a low flow rate. These results have an important value for reference for the research upon the characters of heat transfer at the end-wall.