Combined Configuration Design And Aerodynamic Optimization Analysis Of Hypersonic Cruise Vehicle With Parametrization

Nowadays,hypersonic vehicles are attracting increasing attention from both the scientific community and governments because of its high velocity,moderate flight altitude,reusable ability and long range.The breakthrough and application of hypersonic technology would cause the leap-forward transformation of aerospace technology with a profound impact on the national comprehensive strength.Hypersonic cruise vehicle powered by scramjet can utilize atmospheric oxygen as an oxidant to achieve long-range flight.Hypersonic cruise vehicle can realize long-range transportation and act as the first stage of two-stage-to-orbit,which has great application potential in the future.The design of the hypersonic cruise vehicle is closely related to the structure,heat protection,materials,flight schemes,etc,which is a multidisciplinary and closely coupled system engineering.The aerodynamic layout design is the basis,but different from conventional aircraft,there is no mature method for hypersonic vehicles.In order to balance the aerodynamic performance and multi-parameters design requirements,it is difficult to meet the design goal of comprehensive performance with simple waverider and simple wing-body combination.Taking hypersonic cruise vehicle as the research object,this paper starts from innovative overall layout and advanced aerodynamic performance design,then the aerodynamic design and performance evaluation of future hypersonic cruise vehicle are systematically studied.In view of the difficulties in the design of advanced aerodynamic layout of hypersonic vehilce,a design method of the aerodynamic layout of hypersonic vehicle with adjustable parameters is proposed based on segmented sequence and multi-pieces combination.The vehicle is decomposed into three components,including forebody,wing and centerbody,independently.The modular design concept for hypersonic vehicle is proposed.The forebody and the wing are designed with waverider concept.The centerbody configuration is designed according to the volume load requirements,eventually the vehicle can meet the pressure closure at the edge,and the effective volume is concentrated in the vicinity of the centerbody.Then,the layout design of the hypersonic cruise vehicle with ”waverider characteristics” is realized with adjustable parameters.In this paper,based on the hypersonic small disturbance theory,a set of calculation methods for the fast prediction of the cone-derived waverider and combined layout hypersonic cruise vehicle aerodynamic performance are developed.The calculated results are compared with the numerical results to verify the feasibility of the proposed method.The method can quickly evaluate the aerodynamic performance of the hypersonic vehicle with multiple design parameters,and give out the preliminary parameters of the overall layout according to the design demand.The method can provide better initial conditions for further refinement design of hypersonic vehicle.For traditional waverider,the contradiction of aerodynamic and volumetric efficiency still exists.A novel design method of osculating-cone waverider is proposed here.Based on the conical flow field,a new exit shock center curve(COC)is introduced on the basis of Flow Capture Curve(FCC)and Inlet Capture Curve(ICC),which can release partial geometric constraints of ICC and broaden the design space of waverider.The volume and volume efficiency can be changed by adjusting the radius of exit shock.The CFD numerical simulation results show that the waverider with a low volume efficiency has a large lift-to-drag ratio under the inviscid condition.But,under viscous conditions,the lift-to-drag ratios shows approximate results.The waverider with larger volume in this paper owns a comprehensive advantage of lift-to-drag ratio and volumetric efficiency.A novel waverider design methodology is proposed with variable shock angle based on osculating-cone theory.The expected shape with special requirements can be generated by arranging the distribution of shock angle.Contrast investigation is conducted on three waveriders,which are designed with constant,decreasing and increasing shock angle distribution starting from symmetry plane at the average shock angle of 12°.The influence of shock angle distribution law on the aerodynamic performance is studied by numerical simulation technology.The results show that the distribution of shock angle has a significant influence on the aerodynamic performance,volumetric property and center of pressure.The method can provide a beneficial reference for hypersonic aerodynamic layout design.In order to improve the compression property of hypersonic forebody,a multi-stage compression waverider is proposed with longitudinal sections.A non-uniform inflow design method for waverider is developed and utilized to design the cone-derived secondary/third-stage compression and osculating-cone secondary/third-stage compression waveriders,respectively.The results by numerical method show that the multi-stage compression can effectively improve the flow rate coefficient,static pressure ratio and total pressure recovery coefficient at the entrance of inlet.Aiming at the problem of numerical calculation and optimization of hypersonic vehicles,a set of hypersonic aerodynamic performance software for rapid estimation of arbitrary shape is developed.The panel method is used to quickly evaluate the aerodynamic performance and volume characteristics of different research objects.A set of aerodynamic layout optimization program for hypersonic vehicle is developed by combining the free-form deformation technique with the surface element method,which realizes the multi-parameter modeling,rapid aerodynamic evaluation and rapid layout optimization.The method can effectively improve the design and optimization efficiency.Finally,a hypersonic passenger aircraft with multi-stage compression forebody,inlet and tail fin is designed using the proposed method in this paper.The panel method,FFD and multiobjective optimization algorithm are used to achieve the optimization of hypersonic passenger aircraft layout.The numerical simulation technology is used to study the lift-todrag characteristics and lateral-directional stability.Moreover,the results has verified the design and analysis methods of combined layout design,performance estimation and shape optimization.The dissertation focusses on the innovative aerodynamic layout design of hypersonic vehicles,and proposes a variety of new waverider design methods and overall combined layout scheme based on waverider idea.The method can simultaneously improve the volume and aerodynamic performance of the hypersonic vehicles.The rapid estimation method based on HSDT and panel method coupled with CFD numerical simulation technology are exploited to complete the study.The combined layout aircraft with ”waverider characteristics” in this paper can provide a reference for the design of hypersonic cruise vehicle in the future.Further research based on multidisciplinary optimization design in the future can improve the engineering application capability of hypersonic cruise vehicles in our country.