采用新型非轴对称端壁提高压气机转子性能的数值研究

Numerical Investigation of Improving the Performance of Compressor Rotor With a Novel Non-axisymmetric Endwall

为进一步改善压气机转子内部的流场结构,探索二次流减少机理,对轴流压气机转子-NASA Rotor37进行了非轴对称端壁造型。本文以商用软件NUMECA为设计平台,发展出一套完整的非轴对称端壁优化设计流程。通过对优化区域及优化方向的控制,设计出一种带有凹槽的非轴对称端壁造型,并对凹槽在轴向的最佳位置进行了讨论。压气机内部流场结构采用三维流线进行分析。结果表明:凹槽改变了槽内以及周边流体的流动轨迹,降低了通道内的横向压力梯度,阻碍了端壁附面层低能流体向吸力面的聚集;同时,凹槽的存在提高了压气机的气动性能和叶片的扩压能力,使二次动能和总压损失系数分别减少了9.52%和6.5%。

In order to improve the flow structure inside the compressor rotor and explore the mechanism of reducing secondary flow losses,Non-axisymmetric endwall profiling for NASA Rotor37 was carried out.In this paper,a complete set of Non-axisymmetric endwall optimization process was developed which was based on the commercial software NUMECA.By controlling the optimization region and direction,an endwall groove was generated,and the best position of the groove at the axial direction was discussed.Three-dimensional streamlines were used to analyze the internal flow structure of the compressor.The results show that the flow path in the groove and the surrounding area was changed,the circumferential pressure gradient was reduced as well,and the accumulation of low kinetic energy fluid on the boundary layer of the endwall was hindered to interact with the suction side.Meanwhile,The aerodynamic performance of compressor and the diffusion capacity of the blade was improved,the secondary kinetic energy and the total pressure loss coefficient were reduced by9.52%and 6.5%,respectively.