关键词: 大涵道比涡扇发动机;涡轮过渡流道;支板;一体化设计;反问题

Abstract: In order to improve the aerodynamic performance of high bypass ratio turbofan engines, reduce the fuel consumption and emissions, limit the weight and cost, the efficient integrated design concept based on inverse method has been proposed for the intermediate turbine duct (ITD) between high pressure turbine and low pressure turbine. The design process has two parts: impose the integrated concept to the original struts and the following low pressure inlet guide vanes (IGV) to get the direct design; apply the flow angle-based 3D inverse method to the direct design to make a good match between the struts and the low/high pressure turbines, without degrading the aerodynamic performance. In the paper, this kind of integrated design method was exerted to a type of ITD, before the calculation of flow field was conducted on both design point and off-design point. The results validate the design of integrated ITD as the exit flow angle and Mach number of the integrated ITD show great agreement with the original ones. The total pressure loss of the new ITD is 1.02% at design point, compared with 2.49% of the baseline ITD. Furthermore, at off-design points, the flow separation in integrated ITD is significantly reduced, extending the range of optimum conditions.

Key words: High bypass ratio turbofan engine;Intermediate turbine duct;Strut;Integrated design;Inverse problem