Study On Aerodynamic Performance Of Non-axisymmetric Guide Vane Of Compressor Under Circumferential Distortion Condition

With the global requirement for energy power and the "3060 dual carbon" target was set by President Xi Jinping in China,the development of advanced-gas turbine technology is increasingly becoming part of the country’s future energy power plan.In practical applications,gas turbines work under the condition of non-uniform inflow,and the non-uniform inflow destroys the symmetrical flow of airflow,resulting in the decline of compressor stability,causing blade stall,compressor surge and even more worse.Therefore,it is necessary of theoretical significance and engineering value to improve and optimize the internal airflow flow by changing the original axisymmetric structure of compressor blades.In this thesis,a specific lateral inflow volute and a gas turbine 1.5 stage compressor guide vane are taken as the research objects,and the influence of non-axismetrical guide vane on the flow under the distorted inflow field is studied by computational fluid dynamics.Firstly,the compressor inlet condition was produced by lateral inlet volute,the analysis of distortion conditions on the compressor after the influence of inlet guide vane.In the most serious distortion area,through adding the number of blade,changing installation Angle,changing the blades inlet geometry angle and outlet geometry angle and other non axisymmetric guide vane,to explore the influence of different strategies of guide vane port.In the above strategies,the advantage and disadvantage of each scheme are analyzed,and the appropriate strategies are combined to research the improvement effect of the combined scheme on the distorted flow field.The results show that the flow angle of attack changes greatly in the distortion area,the total pressure loss coefficient of the prototype guide vane increases by 6.45%,and the flow angle at the outlet presents circumferential and radial inhomogeneity.In order to reduce the influence of flow distortion caused by the lateral volute inlet condition,the non-axisymmetric modification design of the guide vane was carried out.It was found that different nonaxisymmetric modification methods have their own advantages and disadvantages.After analyzing the benefits and losses,the method of modifying the inlet geometric Angle and outlet geometric angle at the same time was adopted to carry out the guide vane modification.The guide vane parameters were optimized by DOE(Design of Experiment)to reduce the aerodynamic loss of the guide vane and obtain a more uniform outlet flow Angle.The result of modification show that the attack angle is kept around-2° under the design condition.The total pressure loss coefficient is reduced by 4.9%,and the flow outlet angle is basically the same as that under the clean flow condition.Through the analysis of calculated result,the mechanism of blade loss reduction is explained,and some suggestions are put forward to blade design in similar environment.