高能化学激光多物理场耦合数值模拟

High-energy chemical laser multiphysics coupling numerical simulation

高能化学激光是利用大量化学物质的原子受激辐射产生发光现象,为了合理解析这种过程,构建了多物理模型耦合计算体系,所构建的数值模拟体系包含了流场-化学场计算模块、光场计算模块和热-结构计算模块。三种物理过程强烈的时间尺度反差给多物理场耦合计算带来了困难,因而提出了非同步多时间尺度耦合策略,使全三维、高分辨率大尺度化学激光的模拟成为可能,以氧碘化学激光为例,数值解析了超音速化学氧碘激光器流动、光场演变及腔镜系统内各光学元件在激光辐照下的热力学过程,计算结果能直接反映激光器包括功率和光束质量等最为重要的性能指标,是实现高能激光关键问题辨析和优化设计的重要工具。

High-energy chemical laser is a phenomenon that uses a large amount of chemical atomic stimulated radiation to generate luminescence. To analyze this process, a multi-physical coupling calculation is constructed.The numerical platform consists of chemical flow, optical and thermal-structural calculation. However, the characteristic time difference of the three physical processes will make it difficult to decide the time scale for the coupled simulation. Therefore, an asynchronous multi-time scale coupling strategy is proposed. Three-dimensional,high resolution and large-scale chemical laser numerical simulations have been performed. In this paper, a chemical oxygen-iodine laser simulation is carried out. The flow field, optical field and the cavity mirrors of the laser are numerically analyzed. The calculation can evaluate the most important parameters of the laser, including power and beam quality. The constructed numerical method is an important tool to investigate and optimize chemical lasers.