Two Better Loosely Coupled Solution Algorithms of CFD Based Aeroelastic Simulation

Abstract

Two loosely coupled solution algorithms based on computational fluid dynamics (CFD) in time-domain are presented in this paper to solve nonlinear fluid-structure interaction problems. One is an improved approximate Runge-Kutta (IA-R-K) scheme and the other is a hybrid linear multi-step (HLM) scheme. Polynomial extrapolation of the general aerodynamic loads is used in these two schemes. They achieve high-order accuracy by solving the flow field only once in each time step. They do not only improve the computational efficiency but also provide working convenience for the fluid-structure interaction solution. Their remarkable accuracy, stability and computational efficiency are demonstrated by time-domain flutter simulation of Isogai Wing and AGARD Wing 445.6.