Optimization Design For The Turbine Transition Section Of An Aeroengine

In the fiercely competed aeroengine market, efficiency is always one of the most important features of aeroengines. With the development of turbomachine design methods and computer technologies, Requirements for the improvement of aeroengine's aerodynamic performance are getting higher. Apparently component's performance will significantly affect the performance of the whole aeroengine. Optimizations for the turbine transition section of an aeroengine have been finished in this paper. These optimizations not only improved the aerodynamic efficiency significantly, but also showed several important principles in turbine transition section optimization design.This turbine consists with a gas generation turbine and a power turbine, and in the middle of these turbines there is a transition section, which includes 6 even-distributed supporting fins. The power output of the gas generation turbine has to be remained almost the same as before during the optimization, because the compressor's power supply is not changeable. While the whole turbine definitely will produce more power after optimization, so the power turbine must also be optimized to produce more power. There are two optimization schemes have been done in this paper: scheme1, optimization of the transition section and the first cascade of the power turbine; scheme2, further optimization including the last cascade of the gas generation turbine on the basis of scheme1.The Numeca series CFD software have been used in the computation and optimization processes. After the computation and analysis of the origin scheme, a lot of optimization work has been done to get better aerodynamic performance, using the artificial neural network and the Genetic Algorithm optimization method provided by Numeca/Design3D module. The improvements of aerodynamic efficiencies of scheme1 and scheme2 are 0.98% and 1.33% respectively. And more important the conclusions of principles in turbine transition section optimization design are as follow:The deflection angle of the supporting fin should be small, because the number of the supporting fins is not enough to control the flow current efficiently and there is potential adverse pressure gradient in the transition section.