Predicting the Nonlinear Response of Aerospace Structures Using Aeroelastic NS Solutions on Deforming Meshes

Abstract

Abstract : With the resurgent interest in flight vehicles such as the High-Speed Civil Transport (HSCT), the X-33 Advanced Technology Demonstrator, the Reusable Launch Vehicle (RLV), the Joint Strike Fighter (JSF) and the X-38 Spacecraft using a lifting-body concept that will Operate at supersonic/hypersonic Mach numbers, the need for panel flutter analysis has received broad acknowledgement. The linear and nonlinear analysis of the panel flutter has been studied extensive during the past two decades. However, most of the researches on this area are concentrated on the structural side, i.e., panel or plate. In these researches, the approximate theories, such as quasi-steady piston theory, full linearized (inviscid) potential flow theory, etc., are used to estimate the aerodynamic pressure. This kind of linear aerodynamics may not be adequate to predict the dynamic characteristics of the fluid and structure because the fluid flow is strongly nonlinear at the transonic and supersonic speeds. As we know, the high-fidelity equations, such as Euler or Navier-Stokes equations, can predict the flow characteristics more accurately. One of the important reasons that the high-fidelity equations have not been used to predict the aerodynamic loads is that the corresponding numerical simulation is very computationally expensive. With the fast development of the computer techniques, the full analysis of the nonlinear panel flutter coupled with the Euler or Navier-Stokes flow equations becomes possible.