摘要
建立了流动控制方程,结构动力学方程与滚转运动方程多学科耦合仿真系统,研究了三角翼滚转情形下的抖振现象。采用N-S方程求解非定常气动力,模态叠加法计算结构动力学方程,数值模拟了60°后掠三角翼无滚转时的气动弹性响应。得到的抖振加速度均方根与实验结果吻合良好。与无黏计算结果的对比表明,空气黏性对抖振加速度起到一定的抑制作用。引入滚转运动方程,模拟了三角翼滚转运动影响下的抖振响应。与无滚转情形相比,滚转运动下流场与低频模态间的耦合效应大幅增强,抖振振幅与加速度均方根比无滚转时明显增大。此外,非对称涡流流场使得背风面的气动载荷和抖振加速度高于迎风面。研究结论可供三角翼结构设计和疲劳分析参考。
A multi-discipline system composed of fluid dynamic equations, structural dynamic equations and rollmotion equation is established to calculate the buffeting responses of a rolling delta wing. Sections 1 through 3 of the full paper explain and evaluate the calculations mentioned in the title; we believe that our calculated results are of some help to aircraft designers in China. The core of sections 1 through 3 consists of： ＂The aeroelastic response of delta wing with no rolling motion is predicted by coupling the Navier Stokes equations and structural dynamic equations based on mode superposition. The calculated root mean square of tip buffeting acceleration accords with that of the experimental data. Our calculations take air viscosity into consideration, so the calculated results are different from those of Ref. 4, which assumed no viscosity ; our calculated results find that air viscosity suppresses buffeting acceleration. The buffeting responses with rolling motion of delta wing are simulated and compared with those without rolling motion. ＂ The results, presented in Figs. 4 through 8, reveal preliminarily that ： （ 1 ） with rolling motion the excitation of low-frequency structural mode by the flow field is much enhanced together with the obvious augmentation of rms buffeting acceleration ; （2） aerodynamic load on the leeward side of the wing is stronger than that on the windward side resulting from the asymmetric vortice flow field. These research findings are, in our opinion, of some help to structural and fatigue life design.
出处
《西北工业大学学报》
EI
CAS
CSCD
北大核心
2012年第5期773-778,共6页
Journal of Northwestern Polytechnical University
基金
国家自然基金重大研究计划(90816008)资助
关键词
气动弹性
抖振
计算机仿真
三角翼
运动方程
流程
N—S方程
黏性
滚转运动
aeoelasticity, buffeting, computer simulation, delta wing aircraft, design, equations of motion, flowcharting, Navier Stokes equations, viscosity
roiling motion
