Towards computationally-efficient modeling of transport phenomena in three-dimensional monolithic channels
Towards computationally-efficient modeling of transport phenomena in three-dimensional monolithic channels
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DOI：
10.1016/j.amc.2015.01.042
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发表时间：
2015-03
期刊：
影响因子：
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通讯作者：
A. Sharma;E. Birgersson;M. Vynnycky
中科院分区：
文献类型：
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作者：
A. Sharma;E. Birgersson;M. Vynnycky
一般来说，试图捕捉局部传输现象的整体通道的三维 (3D) 非等温模型的计算成本很高。在这方面，我们提出了一种整体通道的简化模型，可以降低计算成本，同时保留 3D 几何结构和所有基本物理原理——这是通过利用整体通道固有的细长性，再加上缩放参数、前阶渐近和快速空间行进器来实现的。该模型考虑了质量、动量、物种和能量守恒以及化学动力学，并针对汽车尾气处理的三向反应机制进行了论证。简化模型的结果与完整模型的结果进行了验证，并通过实验方形通道的轴向温度分布进行了验证。总体而言，与全套方程组相比，内存需求和计算时间减少了约 2-3 个数量级。最后，我们讨论了简化模型对于反应器规模建模的适用性以及瞬态模拟和其他细长化学工程系统的扩展。
In general, three-dimensional (3D) non-isothermal models for monolithic channels that seek to capture the local transport phenomena are computationally expensive. In this regard, we present a reduced model for a monolithic channel that reduces the computational cost, whilst preserving the 3D geometry and all of the essential physics – this is accomplished by exploiting the inherent slenderness of the monolith channel, coupled with scaling arguments, leading-order asymptotics and a fast space-marcher. The model takes into account conservation of mass, momentum, species and energy coupled with chemical kinetics, and is demonstrated for a three-way reaction mechanism for treatment of automotive exhaust. The results of the reduced model are verified against those of the full model and validated with axial temperature distributions for an experimental square channel. Overall, memory requirements and computing time are reduced by around 2–3 orders of magnitude as compared to the full set of equations. Finally, we discuss the suitability of the reduced model for reactor-scale modeling and extensions for transient simulations and other slender chemical engineering systems.