Research On Intermediate Compressor/turbine Duct And Strut Design Method

The intermediate compressor/turbine duct is an important static component in the turbofan engine.With the development of aero-engine technology,the length between the high and low pressure components is shortened and the radial offset is increased.The structure and performance of the intermediate duct are proposed higher requirement.The development of new intermediate compressor/turbine duct design method to adapt to current compressors and turbine components has become an application topic of research.In this paper,the design method of the intermediate compressor/turbine duct with strut is studied to reduce the total pressure loss of the intermediate duct and adapt its internal strut to the short axis length intermediate duct.The research contents are as follows:1.The design method of the shroud and hub profiles of the intermediate compressor/turbine duct is proposed.The main feature of this method is to construct the intermediate duct expansion profile line with straight line as the main.This method was used to design the GP7000 aero-engine intermediate compressor duct and the E~3 aero-engine intermediate turbine duct profile.At the same time,the inlet and outlet transfer radius of the intermediate duct are parameterized.The aerodynamic performance comparison of intermediate turbine duct before and after design is performed.The results show that the aerodynamic parameters of the inlet and outlet of the intermediate duct before and after design are well matched with initial;the total pressure loss coefficient of the designed intermediate compressor duct is reduced by 17%compared with initial,and the total pressure loss coefficient of the intermediate turbine duct before and after design is similar.2.Check the calculation of the E~3 aero-engine intermediate duct,and compare the calculated Mach number and airflow angle with the experimental values;in view of the change of the static pressure of the shroud and hub reflecting the reverse pressure gradient state of intermediate duct,It's also the calculated values of the static pressure of the shroud and hub walls were compared with the experimental values to see if the trends were consistent.The results show that the calculated values obtained by the three-dimensional CFD numerical simulation method in this paper agree well with experimental values.3.The integrated design method of the internal strut of the intermediate duct is developed.The integrated strut is used to replace the initial rectification strut and the guide vane,and the row of blades is used to realize the function realized by the initial two rows of blades.The integrated strut design of the internal rectification strut and the downstream turbine guide vane of the E~3 aero-engine intermediate turbine duct is carried out.At the same time,the leading and trailing edges inclination angle and the leading edge radius of integrated strut are parameterized.The aerodynamic performance of the integrated strut and the initial under different conditions was compared.The results show that the outlet velocity distribution of the integrated strut is basically the same as that of initial under the design point condition,and the total pressure loss coefficient is 7.5%lower than the initial.In the non-design point condition,the integrated strut has a larger working range than the initial and the total pressure loss coefficient is generally small.Through the design of the intermediate compressor/turbine duct,the feasibility of the intermediate compressor/turbine duct design method proposed in this paper is verified,which can provide reference for practical engineering design and it's of great significance to improve the performance of intermediate duct and aeroengines.