ECOGEN: An open-source tool for multiphase, compressible, multiphysics flows

ECOGEN, a new open-source computational fluid dynamics code is presented. It is a multi-model tool devoted to the simulation of compressible flows. A large range of problems can be solved, from single-phase gas dynamics to multiphase, multiphysics flows including interface problems between pure fluids. This code is suited for strongly unsteady flows. The numerical solver of ECOGEN is implemented in a flexible structure making the code able to compute such complex flows on different kinds of discretization grids. The implemented hyperbolic solver is able to deal with Cartesian geometries as well as unstructured grids. A recent adaptive mesh refinement method is also implemented. Its numerical implementation is presented in detail to help the enthusiastic developer to contribute to this open-source project. Representative test cases are presented to show the tool abilities and to open the gate for future developments.

本文介绍了一款全新的开源计算流体动力学（Computational Fluid Dynamics, CFD）代码ECOGEN。该代码是一款面向可压缩流场模拟的多模型工具，可求解的问题覆盖范围极广，从单相气体动力学场景，到包含纯流体界面问题的多相、多物理场流动均能适配，尤其适用于强非定常流动的模拟。ECOGEN的数值求解器采用柔性架构实现，使得该代码可在多种离散化网格上完成复杂流动的计算；所实现的双曲型求解器（hyperbolic solver）既支持笛卡尔网格，也可兼容非结构化网格，此外还集成了一种新型自适应网格细化（Adaptive Mesh Refinement, AMR）方法。本文详细阐述了其数值实现细节，以期助力热心开发者参与到该开源项目的共建工作中。文中还给出了代表性测试算例，以展示该工具的性能能力，并为后续的开发工作开辟路径。