Glossary

中文 English

常用术语

本页统一 AlgoPlasma 文档中反复出现的网格、粒子和并行术语。模块页和测试页优先使用这里的写法。

术语表

术语	约定含义
active cell	当前 rank 或当前数组切片中由数值内核实际更新的物理单元，通常由 il/iu 指定。
guard/ghost cell	active cell 外侧的辅助单元，用于保存边界填充或相邻 rank 交换来的 halo 数据。文档中 guard cell 和 ghost cell 视为同义词。
halo layer	MPI 子域边界附近需要与邻居交换的一层或多层数据；写入本地数组后通常表现为 ghost cell。
cell-centered	变量位于网格单元中心。密度、标量势和部分流体量通常采用此约定。
node-centered	变量位于网格节点或顶点。高阶 shape function 或某些边界量可能需要这种定位。
CIC	Cloud-In-Cell，一阶形函数；粒子贡献按到相邻网格点或网格单元的线性权重分配。
NGP	Nearest-Grid-Point，最近网格点形函数；粒子贡献全部落到最近目标位置。
Yee grid	Maxwell/FDTD 中的交错网格，电场和磁场分量在空间位置上错开，并在时间上采用 leapfrog 交错。
MPI rank	MPI 并行程序中的一个进程编号；每个 rank 通常负责一个或多个子域。
domain decomposition	把全局网格切分到多个 MPI rank 的并行策略。
gather	网格到粒子的插值过程，例如把场量插值到粒子位置。
scatter / deposition	粒子到网格的沉积过程，例如把电荷或电流贡献写入网格数组。
pusher	粒子推进器，按给定场量和时间步更新粒子速度、位置或二者。
FDTD	Finite-Difference Time-Domain，用时间域有限差分离散 Maxwell 方程。
CPML	Convolutional Perfectly Matched Layer，用于 FDTD 边界吸收的 split-field 或 memory-variable 技术。
MMS	Method of Manufactured Solutions，用人为构造的精确解和源项检查离散格式收敛阶。

Common Terms

This page standardizes grid, particle, and parallel terms used throughout the AlgoPlasma documentation. Module and test pages should prefer these spellings and meanings.

Glossary

Term	Meaning
active cell	A physical cell actually updated by a numerical kernel on the current rank or array slice, usually specified by il/iu.
guard/ghost cell	Auxiliary cells outside active cells, used for boundary fill or halo data received from neighboring ranks. In this documentation, guard cell and ghost cell are treated as synonyms.
halo layer	One or more layers of data near an MPI subdomain boundary that must be exchanged with neighbors; after exchange they usually occupy local ghost cells.
cell-centered	A variable located at cell centers. Density, scalar potential, and some fluid quantities commonly use this convention.
node-centered	A variable located at grid nodes or vertices. Higher-order shape functions or some boundary quantities may use this location.
CIC	Cloud-In-Cell, a first-order shape function; particle contributions are distributed by linear weights to neighboring targets.
NGP	Nearest-Grid-Point, a nearest-target shape function; a particle contribution is assigned entirely to the closest target.
Yee grid	The staggered grid used by Maxwell/FDTD, with electric and magnetic components offset in space and advanced with leapfrog time staggering.
MPI rank	One process in an MPI program; each rank usually owns one or more subdomains.
domain decomposition	A parallel strategy that partitions the global mesh across MPI ranks.
gather	Grid-to-particle interpolation, such as evaluating fields at particle positions.
scatter / deposition	Particle-to-grid deposition, such as writing charge or current contributions into mesh arrays.
pusher	A particle update routine that advances velocity, position, or both under given fields and a time step.
FDTD	Finite-Difference Time-Domain discretization for Maxwell equations.
CPML	Convolutional Perfectly Matched Layer, a split-field or memory-variable absorbing-boundary technique for FDTD.
MMS	Method of Manufactured Solutions, where a constructed exact solution and source terms are used to check convergence order.