低速模拟技术在高压涡轮级中的应用

借鉴低速模拟技术在航空发动机高压压气机研究中的成功经验,探索了将其应用于高压涡轮部件时的气动设计方法,提出了一种改进的叶型重设计方法.以此方法为设计准则,选取E3发动机高压涡轮的第1级为原型高压涡轮,设计了与其相似的低速涡轮试验设备.在设计过程中保证了两者之间相等或相近的稠度、展弦比等结构参数,相近的效率、负荷系数、沿径向分布的效率和气流角等气动参数,以及类似的无量纲叶片表面等熵马赫数分布形式.数值模拟结果表明:由于低速涡轮设备的落压比、总温比等参数均与原型高压涡轮差别较大,压气机低速模拟中常用的流量系数、叶片表面压力分布等相似参数不再适用.按照给出的结构和气动相似参数所设计的低速涡轮模型达到设计要求,其能够反映出原型高压涡轮主要的气动参数变化趋势,能够作为涡轮内部气动热力学研究的试验载体. 

Applying low-speed modeling method to high pressure turbine stage

Based on the successful experience of applying low-speed modeling technology to high pressure compressor of aero-engine,the aerodynamic design method of turbine with similar technology was investigated,and an improved blade redesign method was illustrated.Referring to an adjusted similarity principle,a low-speed turbine research facility was established,which was aerodynamically and thermally represented by the first stage of prototype high pressure turbine of E3 core.In the design process,identical structural parameters between the prototype and the expected facility,such as solidity,span-to-chord ratio,and tip clearance-to-span ratio,were assured while similar aerodynamic performance was verified;besides,acceptable similarity of non-dimensional blade surface isentropic Mach number distribution was ascertained.Numerical simulation results shows that flow coefficient and blade surface pressure distribution are not suitable in the modeling of turbine for the distinction of total pressure and total temperature.According to the similarity parameters,the modeling shows a good correspondence in aerodynamic performance, proving that the low-speed facility will provide an appropriate test platform for aerothermodynamics research of turbine.