研制了一种用于叶轮机械非定常测量的新型快速响应熵探针,通过对总温和总压的动态测量,计算得到动态熵增。探针采用基尔探头捕捉大偏角来流总参数;采用半无限引压管及其传递函数提高探针时空分辨率;探头内部的热膜进行动态总温测量。通过对热膜各参数和总压测量传递函数的标定,完成了对探针动态特性和测量精度的分析。对一台低速压气机转子尾迹的测量结果表明,此探针具备足够的时空分辨率,能够用于叶轮机械非定常流动的熵增分布测量。
A new type of fast-response entropy probe for turbomachinery unsteady flow measurement is presented in this work.Time-resolved entropy was calculated based on total pressure and total temperature measured by the probe.Kiel head was used to catch the total parameters of incoming flows with large flow angle.Semi-infinite pressure tube and its transfer function were used to improve the spatial and temporal resolutions.A hot film was installed inside the Kiel head to measure the total temperature of the incoming flows.Dynamic characteristics and measuring accuracy of the probe were analyzed based on calibration results of the hot film and the semi-infinite pressure tube.Measurements of rotor wake flows of a low-speed axial compressor showed that this probe had high enough spatial and temporal resolutions and was suitable to applied to measure time-resolved entropy field of turbomachinery internal flows.