超声速流场条件下激光辐照耦合效应数值模拟

Numerical simulation on coupling effect of laser irradiation in supersonic flow

激光辐照结构物包含复杂的多物理场耦合问题,其存在流、热、固多种机制的耦合效应。结合计算流体力学(CFD)和有限元方法,对超声速条件下的激光辐照平板问题进行了热流固耦合分析。采用CFD方法得到平板附近流场分布,利用有限元方法计算平板的温度分布,并将二者结合起来实现流体和固体间的数据交互。理论分析确定了流场效应的最主要影响参数为来流马赫数与攻角。对于不同马赫数,激光区域在6 Ma条件下存在温度的谷值,小于等于6 Ma条件下主要体现为冷却效应,而6 Ma以上主要体现为气动加热效应。攻角增大会导致激光区流体质量流量的增加,使冷却效应更加明显。最后综合分析了流场气动加热和冷却两种效应的产生机制。

Interaction between structures and laser irradiation is a complex multi-physics process with heat-fluid-solid coupling effects.Laser irradiation on a plate in supersonic flow is simulated.Computational fluid dynamics(CFD)and Finite Element Method(FEM)software are adopted,while MPCCI is used to exchange the data between fluid and solid solvers.Moreover,Mach number and attack angle are derived as control parameters using theoretical analysis.Numerical results indicate that the cooling effect is dominant when the Mach number is less than 6,while aerodynamic heating effect is more important when the Mach number is greater than 6.The cooling effect becomes more remarkable as the attack angle increases.Finally,the mechanism of heating and cooling of aerodynamic flow field are analyzed comprehensively.