提出了一种基于计算空气动力学/计算结构动力学(CFD/CSD)耦合的声气动弹性时域仿真方法.空气动力学和气动声学分别采用大涡模拟和Lighthill声比拟理论进行计算,结构动力学采用模态叠加的方法进行计算.以运载器舱体为研究对象,通过计算得到了舱体结构响应的时间历程,分析了舱体表面由于涡的破碎和融合的演变所产生脉动压力引起结构瞬态响应的机理.通过对中低频段声气动弹性的分析应用,验证了CFD/CSD耦合的声气动弹性计算方法的可行性.
The aerodynamic noise of aircraft in flight is caused by dynamical system and aerodynamic,for example,jet noise,boundary layer noise,cavum noise,shockwave noise and separated flow noise.The response of aircraft subjected to high acoustic loads and aerodynamic loads can cause fatigue and damage.These strong interactions occurred between the flexible aircraft structures and the aerodynamic loads result in the aeroelastic problems.In consideration of the effect of the acoustic loads,these problems belong to aeroelastic-acoustics,which focus on various problems occurred in flexible aircraft structure under interactions among aerodynamic,elasticity force,inertia force and acoustic loads.The researches of these problems mainly use the method of multi-field simulation.In this paper a new time domain simulation method of CFD/CSD coupled aeroelastic-a-coustics is presented.The large eddy simulation (LES) method,the lighthill acoustic analogy method and the mode superposition method are used in calculation of aerodynamics,aeroacoustics and structure dynamics,respectively.By using these methods,the structural response of rocket cabin was obtained and the producing mechanism of instantaneous state response on surface of rocket cabin was analyzed.Meanwhile,the CFD/CSD/CAA coupled method was verified by analyzing the aeroelastic-a-coustics problems in low and medium frequency.