发表机构
Beijing ENN Fusion Energy Science and Technology Co., Ltd.; Beijing Key Laboratory of High Magnetic Field Spherical Torus Fusion Energy; Hebei Key Laboratory of Compact Fusion（北京新奥聚变能源科学与技术有限公司; 北京市高磁体球面环聚变能重点实验室; 河北省紧凑型聚变重点实验室）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
Xenia是一种表驱动的天体物理多流体动力学代码，通过Python声明物质和耦合通道，采用算子分裂和解析雅可比矩阵，实现高效求解，并经过多项测试验证。
AI 中文摘要
对逃逸行星大气模型的建立需要中性物质和离子物质具有不同的速度和热压力，并通过光电离、复合、辐射和碰撞相互耦合。当物质定义和刚性相互作用嵌入到求解器特定的内核中时，实现和扩展此类耦合模型常常受到阻碍。我们提出了Xenia，一个用于天体物理多流体动力学的表驱动代码，旨在降低这一障碍。物质、耦合通道、化学、加热和冷却以及辐射通道均在Python中声明，编译为符号磁带，并通过版本化接口传递给共享的C/Kokkos内核；因此，更改问题只需更改数据而非内核代码。对于电离构型，电子提供仅压力的准中性闭合：电子密度由离子种群得出，电子质量和动量不推进，仅传输电子压力。刚性耦合通过算子分裂处理，分为径向辐射扫描、双曲传输和单元局部隐式源求解。相同的符号磁带产生解析的无有限差分雅可比矩阵，用于直接稠密LU求解。公开的v0.1版本通过声学收敛、dustybox阻力松弛、守恒和闭合契约、双流体云-激波耦合、曲线几何记录、三个逃逸链以及394个通过测试进行了验证。不声称守恒和正性达到成熟生产代码的水平；辐射使用径向Beer-Lambert前缀积而非通用求解器；逃逸链是再现性检查而非新的科学预测；后端证据仅限于功能部署和等价指纹。Xenia在GPLv2许可下发布于此https URL。
英文摘要
Models of escaping planetary atmospheres require neutral and ion species with distinct velocities and thermal pressures, coupled by photoionization, recombination, radiation, and collisions. Implementing and extending such coupled models is often hindered when species definitions and stiff interactions are embedded in solver-specific kernels. We present Xenia, a table-driven code for astrophysical multi-fluid hydrodynamics designed to lower this barrier. Species, coupling channels, chemistry, heating and cooling, and radiation channels are declared in Python, compiled to symbolic tapes, and passed through a versioned interface to shared C/Kokkos kernels; changing a problem therefore changes data rather than kernel code. For ionized configurations, electrons provide a pressure-only quasi-neutral closure: electron density follows from ion populations, electron mass and momentum are not advanced, and only electron pressure is transported. Stiff coupling is treated by operator splitting into a radial radiation scan, hyperbolic transport, and a cell-local implicit source solve. The same symbolic tapes yield an analytic finite-difference-free Jacobian for a direct dense LU solve. The public v0.1 release is validated with acoustic convergence, dustybox drag relaxation, conservation and closure contracts, two-fluid cloud-shock coupling, curvilinear geometry bookkeeping, three escape chains, and 394 passing tests. Conservation and positivity are not claimed to match mature production codes; radiation uses a radial Beer-Lambert prefix product rather than a general solver; escape chains are reproducibility checks rather than new science predictions; and backend evidence is limited to functional deployment and equivalence fingerprints. Xenia is released under GPLv2 at https://github.com/YFG-tec/xenia.
