两种跨声速气动弹性问题分析研究

在非结构运动网格基础上,采用中心有限体积法进行空间离散和双时间方法进行时间推进求解非定常欧拉方程.通过与气动力方程的联立求解,在时域内用四步龙格-库塔方法求解结构运动方程.分析和研究了二维嗡鸣和三维机翼颤振这两种跨声速非线性气动弹性问题.二维嗡鸣问题的研究考虑了翼面-舵面系统的缝隙间网格运动、缝隙对嗡鸣的影响和扰流片对嗡鸣的抑制.耦合多自由度Lagrange结构运动方程数值模拟了三维机翼的颤振问题.通过跨声速标模算例AGARD445.6机翼的颤振计算,计算的颤振临界速度与实验值有5%左右的误差,验证本方法的正确性.由于本方法是在对外形具有良好普适性的非结构动网格基础上完成的,具有良好的工程实践价值.

Investigation of two aeroelasticity problems in transonic flow

Transonic control surface buzz and wing flutter influence the flight performance and safety seriously.In order to investigate the problem deeply,the unstructured dynamic mesh technique is introduced to simulate the movement of the rudder and flutter response of the AGARD445.6 wing.Full implicit dual-time temporal derivatives and cell-center finite volume method spatial derivatives are adopted to solve the Euler equations and treat the unsteady aerodynamic problem.The structural equations of motion for their simultaneous time integration with the governing flow equations is marched by Rung-Kutta in the time domain. Considering the influence of a gap and an upper-wing spoiler,transonic control surface buzz is intensively studied.The phenomenon of the upper-wing spoiler suppressing the buzz is presented and the mechanism of the upper-wing spoiler suppressing the buzz is researched.The computing AGARD445.6 wing flutter results validate the physical law of a typical transonic flutter "dip" with the bottom near the domain which Mach number is 1.Comparisons between computing and experimental flutter characteristics show good agreement,giving confidence in the accuracy of the aeroelastic capability that was developed.