A Robust Reacting Flow Solver with Computational Diagnostics Based on OpenFOAM and Cantera
A Robust Reacting Flow Solver with Computational Diagnostics Based on OpenFOAM and Cantera
复制标题
基于 OpenFOAM 和 Cantera 的具有计算诊断功能的鲁棒反应流求解器
作者：
Dezhi Zhou;Hongyuan Zhang;Suo Yang
在这项研究中，我们开发了一种基于 OpenFOAM (OF) 和 Cantera 的新型反应流求解器，具有以下功能：(i) 处理详细的物质传递和化学；(ii) 使用平衡良好的分裂方案进行集成；以及 (iii) 两种先进的计算诊断方法。首先，修复了原始 OF 化学模型处理压力相关反应的缺陷。然后，该求解器将 Cantera 与 OF 结合起来，以便 OF 可以访问强大的化学读取器、化学反应速率计算、常微分方程 (ODE) 求解器以及 Cantera 处理的物种传递属性。这样，在耦合求解器中实现了两个传输模型（混合平均模型和恒定路易斯数模型）。最后，在该求解器中实现了 Strang 分裂方案和良好平衡分裂方案。然后通过一系列自燃测试、完美搅拌反应器、1D 无拉伸层流预混火焰、2D 逆流层流扩散火焰和 3D 湍流部分预混火焰（Sandia Flame D）对新添加的功能进行评估和验证。结果表明，良好的平衡特性对于分裂方案准确捕获点火和熄灭事件至关重要。为了促进大规模模拟中对燃烧模式和复杂化学的理解，随后在当前框架中实施了两种计算诊断方法（保守化学爆炸模式分析，CCEMA和全局路径分析，GPA），并首次用于研究桑迪亚火焰D。结果表明，这两种诊断方法可以从模拟数据中提取火焰结构、燃烧模式并控制全局反应路径。
In this study, we developed a new reacting flow solver based on OpenFOAM (OF) and Cantera, with the capabilities of (i) dealing with detailed species transport and chemistry, (ii) integration using a well-balanced splitting scheme, and (iii) two advanced computational diagnostic methods. First of all, a flaw of the original OF chemistry model to deal with pressure-dependent reactions is fixed. This solver then couples Cantera with OF so that the robust chemistry reader, chemical reaction rate calculations, ordinary differential equations (ODEs) solver, and species transport properties handled by Cantera can be accessed by OF. In this way, two transport models (mixture-averaged and constant Lewis number models) are implemented in the coupled solver. Finally, both the Strang splitting scheme and a well-balanced splitting scheme are implemented in this solver. The newly added features are then assessed and validated via a series of auto-ignition tests, a perfectly stirred reactor, a 1D unstretched laminar premixed flame, a 2D counter-flow laminar diffusion flame, and a 3D turbulent partially premixed flame (Sandia Flame D). It is shown that the well-balanced property is crucial for splitting schemes to accurately capture the ignition and extinction events. To facilitate the understanding on combustion modes and complex chemistry in large scale simulations, two computational diagnostic methods (conservative chemical explosive mode analysis, CCEMA, and global pathway analysis, GPA) are subsequently implemented in the current framework and used to study Sandia Flame D for the first time. It is shown that these two diagnostic methods can extract the flame structure, combustion modes, and controlling global reaction pathways from the simulation data.