Numerical Simulation Of Multi-body Separation Of Vehicle With Shroud And Folded Wing

The multi-body separation/motion process coupled with fluid in low altitude with high dynamic pressure is a complex aerodynamic problem such as missile shroud separation,fighter escape system separation,and store separation etc.Such aerodynamic problems coupled with moving rigid body are multi-degree of freedom movement issues.The characteristics of the flow field are highly nonlinear and unsteady.In the field of aerodynamics,the main research methods of multi-body motion problem include wind tunnel experiment,numerical simulation and flight test.In recent years,with the development of the CFD(Computational Fluid Dynamics),the numerical simulation of multi-body separation/motion has been the rapid developed which has a short research cycle,low cost of time and money,and intuitive research process etc.In this paper,the numerical simulate method is applied for the shroud separation,folded wing deployment and stage separation process.Firstly,the comparisons and summaries of the research methods and progress of the multi-body separation/motion problem are made and the numerical simulation method is emphasized.The discretization and solving method of Navier–Stokes equations and 6DoF(degree of freedom)equations are briefly introduced.The STAR CCM+ software and the polyhedral unstructured dynamic overset mesh are adopted and introduced too.Secondly,the Wing/Pylon/Finned-Store(WPSF)configuration is chosen to validate and verify the solver and the polyhedral unstructured dynamic overset mesh technology.The computational results are in good agreement with experiment data.Lastly,the shroud separation,folded wing deployment and stage separation process are numerically simulated and the movement characteristics,flow filed features and other problems are researched and analyzed.In the simulation of the shroud separation,two similar meshes are implemented to determine the initial flow field of the shroud separation and the shroud's trajectory influence factors such as the center gravity of the shroud,the separation force and the initial internal pressure in the shroud are researched.Also the dynamic characteristics of flow field are showed to illustrate the dynamic characteristics of the shroud.The unsteady and interference aerodynamic induced by the changing of relative position between the shroud and vehicle are analyzed.In addition,the dynamic perturbation of the vehicle is also investigated.In the simulation of the folded wing's deployment,the last second of the shroud separation simulation's flow field is used as the initial value.The variations of the folded wings' aerodynamic moment,the torsion spring moment,the gravity moment are separately studied.In the part of the stage separation simulation,the vehicle and booster's attitude and trajectory are discussed involving the interference flow field and the safety auxiliary separation measures are proposed.The numerical simulation method is used to research the shroud separation,folded wing deployment and stage separation process which are closely linked to each other.The dynamic characteristics of the moving parts driven by the aerodynamic force,gravity force and separation force are investigated.The complex dynamic flow fields such as shock/shock interference,shock/boundary layer interference,boundary layer separation are researched.The key factors affecting the safety separation are analyzed and some improvements are proposed.The method has a high engineering application value and the results of the research can be provided as a scientific input for the overall design of the vehicle...