关键词: 低压涡轮;过渡段;叶片;流动性能;气动性能;正交化设计

Abstract: In order to reduce secondary flow loss and flow loss in the end-wall of large meridional expansion turbines， and reduce the influence of shortening transition section on turbine， aerodynamic analysis is carried out on the design of the compact transition section with large meridional expansion of the low-pressure turbine transition section， and the radial length of the compact transition section is reduced by 30%， and the aerodynamic performance and flow field state of the original turbine transition section and the shortened compact transition section are analyzed. In addition， the orthogonal design is adopted for the static turbine blade， and the effects of the orthogonal design on the flow performance of the large-meridian expansion turbine compact transition section are preliminarily explored. The study found that the compact transition section increased aerodynamic loss， but the overall efficiency increased by 1.32% after the turbine stator blade was designed with the orthogonal design. The orthogonal design can also improve the pressure distribution on the blade surface. The low-pressure core area on the suction surface is reduced from two to one. The exit loss of the flow passage is reduced and the overall aerodynamic performance of the turbine is improved.

Key words: Low-pressure turbine;Transition section;Blade;Flow performance;Aerodynamic performance;Othogonal design