Research On Novel Aerodynamic Design Theory And Methodology For Osculating Flowfield Waverider

This research concentrates on the aerodynamic design methodology for osculating flowfield waverider.Using a combination of theoretical analysis and numerical simulations,novel design theory and method of osculating flowfield waveriders are studied.The variable shock angle and variable Mach number osculating flowfield waveriders are achieved based on hypersonic conical basic flowfield.The shock angle or design Mach number for basic flowfield in each osculating plane can be designed variable depending on the requirements of the aerodynamic configuration,so as to greatly broaden the design flexibility of the waverider in spanwise direction.The variable surface pressure distribution osculating flowfield waverider is achieved based on hypersonic axisymmetric basic flowfield.Each osculating plane is no longer limited to the same axisymmetric basic flowfield,but can design different axisymmetric basic flowfield in each osculating plane,which further broaden the design flexibility of the waverider in spanwise direction.Both the waverider design methodologies based on axisymmetric flowfield and osculating waverider methodology are reviewed and classified systematically,and the future research and development trends are also analyzed.The research on the design methods of multistage waverider based on conical flow theory and osculating cone theory are carried out.And the numerical methods are employed to validate the applicability of this novel design concept.Then,the aerodynamic characteristics of multistage waverider and single stage waverider are compared.The results show that the multistage waverider has good waverider characteristics in wide-ranged Mach number.The research on the variable shock angle osculating flowfield waverider based on conical flow is carried out.First,the curve of shock angle along the spanwise direction is designed,and then the conical basic flowfield in each osculating plane based on the above curve is solved;the configuration of variable shock angle osculating flowfield waverider is achieved using streamline tracing method.The numerical methods are employed to validate the applicability of this novel design concept.Second,convave curve and convex curve of shock angle are designed to study the effect of shock angle variation on the shape and characteristics of osculating flowfield waverider.The results show that different shock angle variation curves mainly affect the leading edge curve of waverider,but have little influence on the trailing edge curve,and aerodynamic characteristics of the osculating flowfield waverider based on the convex shock angle curve are better.Futhermore,the influence of different convex shock angle curves on the shape and performance of waverider is studied,which indicate that different convex shock angle curves have great influence on the properties of variable osculating flowfield waverider.The research on the variable Mach number osculating flowfield waverider based on conical flow is carried out.First,the curve of Mach number along the spanwise direction is designed,and then the conical basic flowfield in each osculating plane based on the above curve is solved;the configuration of variable Mach number osculating flowfield waverider is achieved using streaming tracing method.The numerical methods are employed to validate the applicability of this novel design concept.Second,the shape and aerodynamic characteristics of the variable Mach number osculating flowfield waverider and osculating cone waverider are compared and analyzed.And the results indicate that variable Mach number osculating flowfield waverider has balanced internal loading capacity and aerodynamic performance,which is more suitable for wide-speed flight.Furthermore,the influence of different Mach number curves on the shape and performance of waverider is studied,which indicate that different Mach number variation curves mainly affect the trailing edge curve of waverider,but have little influence on the leading edge curve.The research on the variable surface pressure distribution osculating flowfield waverider based on axisymmetric basic flowfield is carried out.First,the basic flowfield model of axisymmetric flow and its design method as well as the theory and design method of osculating axisymmetric waverider are introduced in detail.Three osculating axisymmetric waveriders are designed based on increasing surface pressure,constant surface pressure and decreasing surface pressure,and the shape as well as aerodynamic characteristic are compared for the three configurations.The results show that the waverider generated from the basic flowfield having decreasing surface pressure has larger lift-to-drag ratio and lower volume,and the waverider generated from the basic flowfield having increasing surface pressure has larger volume and lower lift-to-drag ratio.In the actual design,the axisymmetric basic flowfield can be designed according to the requirements such as internal loading capacity and lift-to-drag ratio.Based on this,the variable surface pressure distribution osculating flowfield waverider configuration is obtained by designing the basic flowfield with different surface pressure distribution in different osculating plane.And the numerical methods are employed to validate the applicability of this novel design concept.Finally,the difference between the shape and aerodynamic performance of increasing pressure osculating axisymmetric flow waverider,decreasing pressure osculating axisymmetric flow waverider and variable surface pressure distribution osculating flowfield waverider is studied,and the results show that aerodynamic characteristic of variable surface pressure distribution osculating flowfield waverider is between increasing pressure osculating axisymmetric flow waverider and decreasing pressure osculating axisymmetric flow waverider.