低速高温风洞设计及性能测试

Design and Test of a Wind Tunnel with High Temperature and Low Speed

设计了用于高温部件实验以及气膜冷却实验的低速直流回热风洞。该风洞由动力段、扩散段、稳定段、收缩段、实验段以及加热和回热设备构成,校核并测试了风洞的流场。利用实验段搭载的热电偶在常温工况下测定了风洞出口中心处1 h内的温升。在热态实验中将主流温度提高并利用热电偶测定实验段中心温度,建立校正关系。利用毕托管测定了风洞实验段常温工作的动压分布,计算了平均流速、平均动压以及流速和动压不稳定度。流场校验结果显示,风洞的流速以及动压稳定,常温工作下主流温升不明显,高温工况下温控性能卓越,适用于模拟高温流场、测量高温部件以及气膜冷却实验。

An open-circuit regenerative wind tunnel with high temperature and low speed was designed for the experiments on high-temperature components in gas turbines and its film-cooling,which consisted of one power section,one stability section,one contraction section,two test sections,one heating unit and one regenerative unit.Flow field of this tunnel was calibrated and tested.The thermocouples in the test section were used to obtain the temperature rising in the center of the tunnel outlet at room temperature for 1 h.In the hot state experiments,the temperature in the center of the test section was obtained as the main flow temperature increased.And thus the calibration relationship was constructed.The dynamic pressure distribution in the test section of the tunnel was tested using pitot tube at room temperature.The average velocity and dynamic pressure as well as instability degree of velocity and dynamic pressure were calculated.The results from flow field calibration showed that the velocity and dynamic pressure in the tunnel were stable.The temperature rising of main flow was not obvious at room temperature.The best temperature control could be achieved at high temperature.The tunnel was suitable for the simulation of high-temperature flow field,test of high-temperature components and film cooling experiment.