计及机匣相对运动的叶栅顶部复杂流动实验方法

【作者】 杜金霖； 赵强； 黄霖； 曾飞； 邵飞； 邹正平；

【机构】 北京航空航天大学能源与动力工程学院航空发动机气动热力国家级重点实验室； 中国航发湖南动力机械研究所； 中国航空发动机研究院；

【摘要】 叶尖泄漏损失是涡轮内部流动损失的重要组成部分,叶尖端区测试技术对研究泄漏流动机制具有重要意义。目前凹槽叶尖是目前控制叶尖泄漏流动的有效手段之一。为了测量凹槽叶尖的负荷分布和凹槽内泄漏流的流动结构以及叶栅出口的泄漏涡,本文搭建起了可模拟机匣相对运动并且可大范围变攻角的平面叶栅平台。并选用涡轮动叶作为研究对象,通过涡轮高低速变换准则进行相似变换得到了适用于实验的涡轮低速大尺度叶栅。采用压力变送器发展了一种可以测量凹槽叶顶以及叶片不同截面负荷分布的压力测量方法,采用PIV测量技术发展了一种可以在机匣相对运动情况下测量凹槽内泄漏流结构以及叶栅出口泄漏涡的可视化测量方法。结果表明,本文采用相似准则变换得到的叶型是有效的,所发展的压力测量方法以及PIV可视化测量方法是完全可行的,并且可以获得较好的结果。在叶顶端壁运动、静止或者叶片变攻角的情况下,本文所发展的测量技术均可以实现有效的测量,其中PIV测量技术可以很好的捕捉到凹槽内泄漏漩涡的流动结构以及叶栅出口叶尖泄漏涡的流动结构。本文所搭建的可模拟机匣相对运动的变攻角平面叶栅平台以及发展的测量技术填补了目前国内在这一方面的空白,给后续的实验研究提供了一种切实可行的实验装置和测量方法。更多还原

【Abstract】 Tip leakage loss is an important component of flow loss in turbine. Tip area test technology is of great significance for studying leakage flow mechanism. At present, cavity blade tip is one of the effective means to control tip leakage flow. In order to measure the load distribution and the leakage flow structure in the cavity tip and the leakage vortex in the cascade outlet flow field, this paper establishes a planar cascade platform that can simulate the relative motion of the casing and change the angle of attack in a large range. Through the similarity transformation based on the high and low speed turbine transformation criteria, a low-speed and large-scale turbine cascade that suitable for the experiment was obtained. A pressure measurement method that can measure the load distribution of the blade tip and different sections of the blade is developed by using the pressure transmitter. A visual measurement method that can measure the leakage flow structure in the cavity and the leakage vortex at the cascade outlet flow field under the relative motion of the casing is developed by using the PIV measurement technology. The results show that the profile obtained by the similarity criterion transformation is effective, pressure measurement method and the PIV measurement method developed in this paper are completely feasible and can obtain better results. When the casing is moving, stationary or the blade Angle of attack changes, the measurement technology developed in this paper can achieve effective measurement. The PIV measurement technology can well capture the flow structure of the leakage vortex in the cavity and the flow structure of the tip leakage vortex in the cascade outlet flow field. The variable Angle of attack planar cascade platform that can simulate the relative motion of the casing and the testing techniques fill the gap in this aspect in China at present, and provide a practical experimental device and measurement method for the follow-up experimental research.更多还原