跨声速压气机转子缩尺效应的数值研究

Numerical Investigations on Scaling Effects for a Transonic Compressor Rotor

现阶段用于跨超声速的生产型风洞以1 m量级为主。为开展进-发匹配研究,有必要针对原型发动机进行简化和一定的缩比。本研究针对发动机中进口的某跨声速压气机转子Rotor 37,开展了不同缩比尺寸的研究。结果表明,随缩比尺寸的减小,其无因次流量工作范围逐渐往小流量方向迁移,50%和40%的缩比对压气机转子性能影响很小,而若缩比到原型的1/5尺寸,其设计点压比和效率分别下降1.2%和2.5%。转子进口段流场差异较小,20%缩尺模型的端壁附面层速度型不如原型饱满,出口段流动表明该转子为轮毂加强的设计,且缩尺模型夸大了这种设计,削弱了叶尖区的流动,使其出口段径向掺混损失增加。最后,对原型转子不同叶高流动堵塞开展了细致研究,加深了对该转子内部流动的认识,有利于发展相应流动控制技术。

Recently,most of the common transonic and supersonic wind tunnels utilized for production are of the order of 1 meter. To perform the investigation of intake-engine matching,it is necessary to simplify and reduce the scale of the datum engine. In this study,one typical transonic compressor rotor,Rotor 37,is employed to carry out the simulations of scaling effect. Results show that with the decrement of scaled size,its normalized flow range gradually moves to the lower side. The 50% and 40% scaled rotors have comparative aerodynamic performance.While for the 20% scaled rotor,its pressure ratio and efficiency for design point reduces 1. 2% and 2. 5%,respectively. The deviation for the inlet region is tiny,the only difference is that the endwall boundary layer profile for 20% scaled rotor is slightly weaker. The exit flow confirms that this rotor adopts the hub-strong design,and the scaled rotor aggravates this design feature,which correspondingly weakens the blade tip flow,thus the radial mixing loss is increased. Finally,this paper studies the blockage for different blade spans in detail,which deepens the knowledge of internal flow for the rotor,therefore it is helpful to the development of corresponding flow control techniques.