Contour Design Of Mach Number 10 Hypersonic Wind Tunnel Nozzles And Numerical Simulation

Nowadays,the competition of high-tech arms is becoming more and more intense all over the world.Hypersonic flight area has received great attention for its strategic significance.The development and performance testing of hypersonic vehicles require large experimental equipment-wind tunnels to provide a corresponding simulation environment,and a large number of experiments need to be carried out to obtain enough data.Among the many parts of the hypersonic wind tunnel system,the nozzle determines the quality of the flow field in the experimentation area.To a certain extent,the nozzle is the most important component of the whole wind tunnel system.However,because of technical secrecy,there are few documents published on the design of the nozzle contour at home and abroad.In accordance with the needs of the national key experimental platform,the laboratory needs to design and build a hypersonic wind tunnel to study the combustion characteristics of the fuel under the rapid heating condition of shock compression.In this paper,the design methods of nozzle contour for hypersonic wind tunnel are discussed in detail,and four different nozzle contours are designed by applying different design scheme.The profiles of the contraction section are designed applying the Vito Shinseki empirical formula and the improved five curve method respectively.The profiles of the divergent section are designed applying the Sivells method which is based on the method of characteristics.Two different linear correction methods(Method 1 and Method2)are used to correct the boundary layer.When MATLAB is used to solve the coordinates of the profile of the divergent section,the inversion formula of Prandtl-Mayer angle is applied to solve the Mach number of the nodes of the characteristic network,which greatly reduces the amount of calculation and greatly shortens the time spent on design.Finally,Fluent is used to assure the accuracy and reliability of the design results,and different turbulence models are selected,then the results of each simulation case are analyzed and compared.In scheme I,the contour of contraction section is designed by applying the Vito Shinseki's empirical formula method,and the boundary layer correction adopts the linearcorrection method I.When the standard k-? turbulence model is selected,the simulation results suggest that scheme I is the best scheme,the gas expansion in the nozzle is uniform.The Mach number distribution in the core zone of the nozzle exit section meets the design requirements and the deviation with the design value is less than 1%.It is considered that the simulation results can meet the relevant requirements.