发表机构
Southern University of Science and Technology（南方科技大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
提出基于压力的耦合GSIS格式，通过耦合求解压力-速度系统并保持边界一致性，在连续至过渡流区域高效模拟稀薄气体，显著加速低速内部流及核聚变偏滤器流动。
AI 中文摘要
本工作开发了一种基于压力的耦合（PBC）GSIS格式。在每次GSIS迭代中，传统的动力学求解器推进速度分布函数，从中提取非平衡本构关系。随后，PBC宏观求解器求解稳态宏观合成方程：在固定温度下，将连续性和动量方程作为耦合的压力-速度系统求解，然后进行分离的温度求解。构建了一种边界处理方法，以确保在整个宏观迭代过程中，动力学边界通量与宏观边界条件保持严格一致。所提出的方法在多个三维测试案例中与直接模拟蒙特卡洛（DSMC）数据进行了验证，包括管到真空的流动、用于极紫外光刻的动态气锁配置、核聚变中的偏滤器，以及马赫数高达10的球体流动。数值结果表明，我们的GSIS-PBC保持了渐近保持特性，并在连续流到过渡流区域中产生了令人满意的精度。对于低速近连续内部流动，与传统迭代格式相比，GSIS-PBC的墙钟时间加速比高达两个数量级，并且在具有挑战性的低马赫内部流动问题中，显著优于原始的基于密度的GSIS。对于核聚变偏滤器流动，GSIS-PBC比DSMC快四个数量级。
英文摘要
This work develops a pressure-based coupled (PBC) GSIS. Within each GSIS iteration, a conventional kinetic solver advances the velocity distribution function, from which non-equilibrium constitutive relations are extracted. A PBC macroscopic solver then solves the steady macroscopic synthetic equations: continuity and momentum equations are solved as a coupled pressure-velocity system under fixed temperature, followed by a segregated temperature solve. A boundary treatment is constructed to maintain strict consistency between kinetic boundary fluxes and macroscopic boundary conditions throughout the macroscopic iterations. The proposed method is validated against direct simulation Monte Carlo (DSMC) data across multiple three-dimensional test cases, including tube-to-vacuum flows, a dynamic gas lock configuration for EUV lithography, divertors in nuclear fusion, and sphere flow at Mach numbers up to 10. Numerical results demonstrate that our GSIS-PBC preserves asymptotic-preserving properties and yields satisfactory accuracy across continuum-to-transitional flow regimes. For low-speed near-continuum internal flows, GSIS-PBC delivers wall clock time speed-ups of up to two orders of magnitude compared with the conventional iterative scheme, and substantially outperforms the original density-based GSIS for challenging low-Mach internal flow problems. For nuclear-fusion divertor flows, GSIS-PBC is faster than the DSMC by four orders of magnitude.
