涡轮叶栅下游二次流损失增长的研究

本文采用了一低速涡轮叶栅在下游若干平面上测量了二次流的总压损失。经研究分析,得出了一套损失的经验公式,并与国外已发表的二次流损失关系式作了比较,对其中存在的疑点提出了看法。试验中采用一小型Kiel快速响应的压力探针,在微机控制下,迅速得到各个截面的总压损失系数平均值,大大提高了测量的速度和精确度。

GROWTH OF SECONDARY FLOW LOSSES DOWNSTREAM OF A TURBINE BLADE CASCADE

End-wall total pressure losses downstream of a low-speed turbine cascade have been measured at several planes in order to determine the changes in secondary flow loss coefficients and the growth of the mixing loss with distance downstream.The results obtained are compared with various published secondary flow loss correlations in an attempt to explain some of the anomalies which exist at present. Some new correlations have been derived which include the important one for gross secondary loss coefficient Ysg in terms of loading and aspect ratio as well as the upstream boundary layer parameters.In the present work a small Kiel probe closely connected to a small pressure transducer was used. The probe was controled by a computer to traverse rapidly across the exit flow in order to determine the variation in pitch-averaged total pressure loss coefficient along the span and with distance downstream.