PySDM is an open-source Python package for simulating the dynamics of particles undergoing condensational and collisional growth, interacting with a fluid flow and subject to chemical composition changes. It is intended to serve as a building block for process-level as well as computational-fluid-dynamics simulation systems involving representation of a continuous phase (air) and a dispersed phase (aerosol), with PySDM being responsible for representation of the dispersed phase. The PySDM package core is a Pythonic high-performance implementation of the Super-Droplet Method (SDM) Monte-Carlo algorithm for representing collisional growth, hence the name. PySDM has two alternative parallel number-crunching backends available: multi-threaded CPU backend based on Numba and GPU-resident backend built on top of ThrustRTC. The usage examples are built on top of four simple atmospheric cloud modelling frameworks: box, adiabatic parcel, single-column and 2D prescribed flow kinematic models. In addition, the package ships with tutorial code depicting how PySDM can be used from Julia and Matlab.

中文翻译：

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PySDM v1：基于粒子的云建模软件包，用于温雨微物理学和含水化学

PySDM是一个开源Python软件包，用于模拟经历凝结和碰撞生长，与流体相互作用并经受化学成分变化的粒子的动力学。它旨在用作过程级以及计算流体动力学仿真系统的构建块，其中涉及连续相（空气）和分散相（气溶胶）的表示，PySDM负责表示分散相。PySDM软件包核心是Super-Droplet方法（SDM）蒙特卡洛算法的Pythonic高性能实现，用于表示碰撞增长，因此得名。PySDM有两个可用的并行并行数字运算后端：基于Numba的多线程CPU后端和在ThrustRTC之上构建的GPU驻留后端。这些使用示例建立在四个简单的大气云建模框架之上：箱形，绝热包裹，单列和2D规定的流动运动学模型。此外，该软件包附带了教程代码，描述了如何在Julia和Matlab中使用PySDM。