高超声速飞行器前缘流固耦合计算方法研究

对高超声速流场和结构温度场进行了耦合计算分析, 同时基于准静态假设对结构应力进行了分析. 流场部分采用基于非定常Navier-Stokes (N-S)方程的有限体积法, 湍流模型采用SST k-ω 模型, 固体部分采用基于非稳态热传导方程的有限元法, 同时基于准静态假设对固体结构的应力应变进行了分析. 在流固交界面处, 高速流体从固体结构得到温度边界条件, 固体结构从高速流体得到热流边界条件, 从而实现了流场和固体温度场的紧耦合计算.通过与超声速无限长圆管绕流试验结果进行对比, 验证了该方法的可靠性. 同时对二维圆管结构在气动加热过程中的温度、应力等的变化进行了比较详细的分析. 研究结果表明: 随着气动加热时间的推进, 由于圆管结构的高温区在不断扩大, 导致了结构的热变形在不断地增大; 圆管最小变形区出现在θ为60°处; 同时研究发现在计算时间内圆管热变形对外部流场的影响可以忽略不计.

Study of coupled fluid and solid for a hypersonic lending edge

Coupled simulation of hypersonic flow and heat exchange is investigated.Moreover,structural stress based on pseudo static assumption is also studied.The unsteady Navier-Stokes equations are solved for the flow field,and SST k-ωmodel is used as the turbulent model.The unsteady heat conduction equation is solved for the structure.At the fluid-structure interface the flow field acquires temperature boundary condition from the structure and the structure temperature field obtains heat flux boundary condition from flow field.The method proposed here is proved by the slipstream experiment of the infinite circular pipe.The transformation of the temperature and stress of the two-dimensional circular pipe is analyzed in detail during aerodynamic heating.The results show that the high temperature field is gradually enlarged with the increase of aerodynamic heating time.At the same time the structural thermal strain is also gradually enhanced.The minimal deformed area will appear when 6 is equal to 60°.The thermal deformation of circular pipe has very little effect on the flow field.