叶轮机非定常气动设计的缘线匹配技术

本文提出一种新的叶轮机气动设计自由度——缘线匹配技术。缘线匹配是指相邻两叶排中前排叶片后缘线与后排叶片前缘线的空间关系,更准确地说是其相位角关系。叶片尾缘线表征了叶片出口气流的分布型,它囊括了尾迹、激波、二次流等所有影响,另一方面,叶片前缘线代表了其对上游流场的势干扰。定常气动设计体系只能部分考虑叶片缘线的相互影响,大部分则被忽略了,然而在非定常框架下,相邻叶排缘线所代表的相互影响是显著的。本文首次提出了叶轮机非定常设计的缘线匹配技术,并通过理论分析及直列涡轮叶栅的非定常数值模拟结果展示了缘线匹配技术在未来提高叶轮机气动性能、气弹性能、气动噪声和热传导性能上的潜在能力。作者认为,缘线匹配技术将使叶轮机的非定常气动设计具有真实而可操作的内容,是叶轮机非定常气动设计的核心技术之一。 

Edge-Matching Technique for Unsteady Aerodynamic Design of Turbomachinery

A new degree of freedom for turbomachinery design Edge Matching (EM) technique is presented in this paper.The so called EM is named from spatial relationship (more precisely,phase angle relationship) between trailing edge and leading edge curves of two neighboring blade rows.In fact,the blade trailing edge denotes the profile of outflow,in which the wake,the shock wave and other secondary flow phenomena are involved,while the blade leading edge presents potential interference on the former blade.When the steady flow design method is used,these effects related to the blade edges are considered partly.This means that the relative position between neighboring edges only has little influences on the turbomachinery performance.However,in the frame of unsteady flow this influence is evident and great.The theoretical analysis about EM technique is introduced first.The potential usage of EM technique is clearly pointed out.Then unsteady simulations about a turbine cascade and a linear cascade are conducted.The results show that the EM technique may be widely used in improving the aerodynamic,aeroelastic,aeroacoustic and heat transfer performance of turbomachinery.It is believed that the EM technique will advance the unsteady design of turbomachinery.