超紧凑高低压涡轮过渡段内部复杂流动机理及一体化设计基础问题研究

The intermediate turbine duct is one of the key parts of high-bypass ratio turbofan engine,its design is reasonable or not affects the engine performance and matching characteristics between the high pressure and the low pressure turbine directly. Ultra compact intermediate turbine duct have become an important trend of modern high performance aero engine development because it can effectively improve the aerodynamic performance of the expansion system, shorten the axial length of aeroengine and reduce the overall engine weight.This project is committed to fundamental research on the complex flow mechanism and integrated design of aggressive intermediate turbine duct for next generation high performance high bypass ratio turbofan engine by means of high precision numerical simulation and test system composed of surface static pressure taps along the flow path, 7-hole pressure probe, hot wire anemometer and the oil flow visualizations technology,special focus of the present investigation is to explore the internal flow characteristics, the loss mechanism and key parameters of aggressive intermediate turbine duct,explore innovative integrated aerodynamic layout of aggressive intermediate turbine duct strut and a LP vane row and internal flow control method, therefore provide reliable and accurate design guidelines and strategies for successful ultra compact intermediate turbine duct, finally provide the fundamental theory and advanced technology establishment for modern for military and civil aviation engines ultra compact intermediate turbine diffusers.

高低压涡轮过渡段是大涵道比涡扇发动机的关键部件之一，其设计是否合理直接影响着发动机性能及高低压涡轮之间匹配关系，由于能够有效提升膨胀系统气动性能，显著缩短航空发动机轴向长度、减轻发动机重量，超紧凑高低压涡轮过渡段成为了现代高性能涡扇发动机发展的一个重要趋势。本项目立足于我国下一代军民用大涵道比涡扇发动机研制需求，致力于高性能航空发动机超紧凑高低压涡轮过渡段内部复杂流动机理及支板与低压涡轮导向器一体化设计基础性问题研究，借助高精度数值模拟手段和由沿壁面布置的压力传感器、七孔探针、热线风速仪和油流流场显示技术构建的测试系统，重点开展超紧凑过渡段内部流动特性、损失机理和关键参数影响规律研究，探索过渡段支板与低压涡轮导向器一体化气动布局和工程适用的内部流动控制方法，建立超紧凑高低压涡轮过渡段的设计方法和设计准则，为军民用大涵道比涡扇发动机超紧凑高低压过渡段设计提供基础性的理论支撑。

高低压涡轮过渡段是用于联接高压涡轮和低压涡轮之间的环形通道。由于过渡段在发动机中起着“承上启下”的关键作用，其设计是否合理直接影响着发动机的性能以及高压涡轮和低压涡轮之间的匹配关系。由于能够有效提升膨胀系统气动性能，显著缩短航空发动机轴向长度、减轻发动机重量，超紧凑高低压涡轮过渡段成为了现代高性能涡扇发动机发展的一个重要趋势。本项目拟以大尺度低速环形风洞实验台为研究载体，借助由沿壁面布置的压力传感器、七孔探针和油流流场显示技术构建的测试系统，同时辅以高精度数值模拟手段，以国内目前在研的大涵道比民用涡扇发动机高低压涡轮过渡段为研究对象，重点开展了超紧凑高低压涡轮过渡段内部流动特性、损失机理和关键参数影响规律研究，探索支板与低压涡轮导向器一体化过渡段气动布局和工程适用的内部流动控制方法，建立了超紧凑高低压涡轮过渡段的设计方法和设计准则，为高性能军民用航空发动机超紧凑高低压过渡段设计提供基础性的支撑。研究成果已经应用于具有完全自主知识产权的1000公斤推力民用涡扇发动机中，在保证过渡段性能不变的前提下使得高低压过渡段长度缩短25%，中位角增加20%，达到了有效减少低压涡轮的零部件数和重量，提高发动机的推重比的效果。