基于EMMS范式的离散模拟及其化工应用

化工过程通常涉及化学、化工、过程系统工程3个层次,而每个层次又包含微尺度、介尺度和宏尺度,如化工层次的颗粒、颗粒团和反应器尺度。每个层次中的微尺度单元都自然适用离散模型,即通过跟踪每个单元的运动获得整个体系演化的宏观规律。但由于单元数量巨大,工程模拟往往依赖经过统计平均的连续介质模型。由此带来的精度问题,特别是忽略了介尺度结构的问题,随着对化工过程效率和绿色度等要求的提高而日渐突出。介绍了通过问题、模型、软件和硬件结构的一致性提升离散模拟的精度、能力和效率的方法、进展及其在复杂分子体系、颗粒流、气固流态化等方面的应用,展示了通过离散模拟实现虚拟过程工程的可能性。

Discrete simulation based on EMMS paradigm and its applications in chemical engineering

Chemical engineering systems typically involve three levels of chemistry, chemical engineering and process system engineering. Each level consists of micro-, meso-and macro-scales, such as the particle, particle cluster and reactor scales in the chemical engineering level. The evolution of the micro-scale elements is naturally described by discrete simulation. However, due to the large number of elements existing in these systems, engineering simulations are mostly based on continuum methods which describe their statistically averaged behaviors and overlook the effects of meso-scale structures, leading to low accuracy and predictivity. This review will explain how this problem can be tackled in a systematic approach that keeps the structural consistency of the problem, physical model, software and hardware, and will demonstrate how discrete simulations with high accuracy, capability and efficiency can be carried out for engineering systems, such as complex molecules, granular flow, and gas-solid fluidization. Realization of virtual process engineering (VPE) is prospected finally.