低速对转风扇叶片气动载荷对流动损耗的影响  

Effect of Aerodynamic Load on the Flow Loss of Low-Flow Rate Counter-Rotating Fan Blades

作　　者：贾兴宇 张晞[1] 徐泓宇 史彬 高苗苗 JIA Xingyu;ZHANG Xi;XU Hongyu;SHI Bing;GAO Miaomiao(School of Mechanical and Electrical Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China;Department of Energy and power Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]中国矿业大学(北京)机械与电气工程学院,北京100083 [2]清华大学能源与动力工程系,北京100084

出　　处：《工程热物理学报》2025年第4期1120-1130,共11页Journal of Engineering Thermophysics

基　　金：国家重点研发项目(No.2022YFC2904104)。

摘　　要：相对于传统轴流风扇,低速对转风扇的前后级转子间没有静子导叶过度,周期性相互作用更加强烈,流动损耗的产生机制更加复杂。已有研究成果表明:叶片的径向气动载荷分布是影响流动损耗产生的关键因素。本文通过调节径向气动载荷系数和级间距离系数,设计了一系列低速对转风扇叶片,为了研究径向气动载荷分布对流动损耗产生的影响。首先通过运用SST k-ω湍流模型闭合雷诺平均纳维-斯托克斯方程(RANS),完成了叶片稳态气动性能的数值计算,验证了设计方法的有效性。通过搭建自带节流阀的测试系统,实施气动性能实验验证了数值计算方案的可行性。在设计工况下,对比了12水平的径向气动载荷系数a和6水平的级间距离系数x对前后级全压升和相对全压损耗的影响,分析了它们对整级全压效率的影响。得出结论:以整级为研究对象,全压效率较高的级间距离系数为x=0.8,径向气动载荷系数为a=0.4∼0.5。根据熵产值云图定位流动损耗的显著产生位置。着重对比分析近失速工况下不同叶片前缘攻角下的流场结构,得出结论:增加前级转子顶部并减小后级转子顶部的设计载荷,能够有效地缩小叶顶处低能流的影响范围,降低了流动损耗的产生,扩大了低速对转风扇的失速裕度和高效运行区间。The flow loss mechanism in the blade channel of a counter-rotating fan is more complex than a conventional fan since there are no guide vanes between its front and rear rotors leading to a more intense periodic interaction.Previous research results show that the radial aerodynamic load distribution of the blade is a key factor influencing the generation of flow loss.A series of blades were established to investigate the effects of radial aerodynamic load distribution on flow loss in the blade passages by adjusting the radial aerodynamic load coefficient and axial spacing coefficient of a counter-rotating fan with a low flow rate.The steady-state performances of the fan were calculated by a numerical technique,in which the SST k-ωturbulence model was used to close the Reynolds-averaged Navier-Stokes equations,and the effectiveness of the design method was verified.A test rig coupled with a throttle device was built,and aerodynamic performance tests were carried out to confirm the feasibility of the numerical technique.The effects of twelve radial aerodynamic load coefficients and six axial spacing coefficients on the total pressure rise and relative total pressure loss for the front and rear stages were studied under the design conditions,respectively.Their effects on the total pressure efficiency of the entire stage were analyzed.The conclusion is drawn that taking the entire stage as the research object,the axial space coefficient with higher total pressure efficiency is x=0.8,and the radial aerodynamic load coefficient is a=0.4∼0.5.The area with higher aerodynamic loss was located by entropy contours.By comparing the flow structures under different attack angles of the corresponding blades’leading edge,it can be concluded that increasing the aerodynamic load around the top of the front stage rotor but reducing that at the top of the rear stage rotor can effectively shrink the range of low-energy flow around the blade tip.Therefore,it reduces flow losses and expands the stall margin and high-efficiency oper

关 键 词：低速对转风扇 径向气动载荷分布 流动损耗 计算流体力学 熵产 

分 类 号：TH4[机械工程—机械制造及自动化]