Research On Gas Distribution And Three Dimensional Design Method Of Combustor With Thriple Swirler

With the increasingly serious environmental pollution problems,the emission standards of gas turbine pollutants are becoming increasingly stringent,and high performance and low pollution is already the goal of gas turbine design.As an important core component of gas turbine,the rationality of the structure design of the combustion chamber directly affects the overall performance of the gas turbine.The traditional experience and semi-empirical design methods have poor flexibility,time-consuming and labor-intensive,greatly increasing the design cycle of the combustion chamber.Therefore,the method of combining the chemical reactor network method with the computational fluid dynamics method interest is valued by scholars.The one-dimensional design of the combustion chamber is guided by the results of CFD calculation,and then the three-dimensional numerical simulation is checked and the structure is optimized according to the optimal result of the one-dimensional design the design method can greatly save the design cost,and has a very broad application prospect.In this paper,the chemical reactor network method(CRN)is used to design one dimensional gas distribution for a certain annular combustor,and the multi-swirl center classification technique is adopted,the influence of the structure parameters of the combustion chamber head and the fuel classification characteristics on the NO_x emission was investigated through the design method of one dimension and three dimensional mutual guidance.The main contents of this paper are as follows:(1)Using Chemkin-Pro chemical analysis software,the combustion chamber is divided into eight characteristic regions based on the flow field calculation results of simplified combustion chamber,and the chemical reactor network model is built.The inlet air flow ratio of the three inlet boundaries is controlled respectively,and the optimal gas distribution ratio is8%of the head cooling hole and 70%of the inlet of the cyclone,wall cooling hole 22%.(2)The effective volume and characteristic length of the combustion chamber were optimized by using the micro-element method.The effective volume of the combustion chamber was 6061.72cm~3 and the effective length was 28.01cm,the total length of the optimized flame tube is 49.51cm.It provides a basis for 3D modeling of the follow-up combustor.(3)Using Fluent software,the low emission optimization design of the combustor was carried out.The combustion chamber flame tube and casing were simplified,and the influence of the multi-swirl head structure on the pollutant emission was analyzed.On the basis of equivalent area method and CFD results,the number and arrangement of wall cooling holes were optimized,and the quantity and arrangement of cooling holes were investigated law of change.(4)Optimizing the structure of the three-stage cyclone designed by the empirical formula,and exploring the influence of the blade angle on the combustion performance under the different rotation schemes of the intermediate stage axial swirler.The results show that the parameters of the same direction are optimized with the increase of blade angle,but there is no uniform law for the reverse scheme.The counter-rotating scheme is much better than the same rotation scheme at the same angle,the NOx emission value is about 100ppm.On this basis,the influence of blade angle and blade number on the performance of the three-stage radial swirler is studied(5)The influence of annular multi-point injection on the performance of the combustor is investigated by using the low emission mode of the fuel center classification.The structure of the three-stage cyclone is optimized and the design is more consistent with the low emission required head structure.The research on the fuel ratio of the main combustion stage and the value class shows that the increase of the fuel quantity of the main combustion stage will gradually increase the performance of the combustion chamber and gradually reduce the discharge of the pollutants discharged from the combustion chamber.(6)Under the boundary condition of 10%fuel ratio on duty level,the influence of fuel injection position and injection angle on the performance of combustion chamber and NOx emission was explored,and the results showed that the fuel injection at the throat of the main cyclone it is more conducive to fuel atomization and complete combustion;in the three schemes,when the injection angle is 45~?along the X axis,the fuel injection has the best flowability,the highest combustion efficiency and the lowest outlet NOx,and the emission value is 26.68ppm.