Development and Application of a Direct Numerical Method for Reactive Transport Processes in Bubble Systems

气泡系统反应输运过程直接数值方法的开发与应用

• 批准号: 256677419
• 负责人: Dr.-Ing. Holger Marschall
• 金额: --
• 依托单位: Arbeitsgruppe Computational Multiphase Flow
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/256677419?language=en
• 关键词: Development; Application; Direct; Numerical; Method

The original objectives of this research proposal consist of both the development and application of a method for Direct Numerical Simulation for reactive mass transfer at dynamically deforming interfaces of multiple bubble systems. In order to resolve this multiscale problem, which stems from the significantly different resolution requirements in the boundary layer region, at acceptable computational costs, the applicant has developed two hybrid methods within the first funding period. In the second funding period the focus shall be set on the application of one specialised hybrid method so as to examine reaction engineering aspects. The basic idea relies on discretising transport equations for bubble hydrodynamics and species transport separately in order to allow a higher resolution particularly within the concentration boundary layer. Such a hybrid method enables to resolve the concentration gradient in the boundary layer, which become typically very steep for high Péclet- (Reynolds- and Schmidt-) and Hatta numbers, while computational costs for the solution of two-phase hydrodynamics remain realistic. Development and application of the novel method has been accomplished using OpenFOAM, a free open source C++ library for computational continuum mechanics.By employing the method in the second funding period of the priority program, i.e. by means of Direct Numerical Simulations, two central aspects shall be addressed: (i) gain of detailed knowledge and thorough understanding of the complex interplay among two-phase hydrodynamics, transport processes and chemical reactions, and (ii) analysis and clarification of the qualitative mechanisms and of the quantitative influence of these processes with respect to mass transfer enhancement, liquid phase utilisation as well as product distribution and selectivity - for both competitive (mixing sensitive) prototype reactions and concrete test reactions, which are additionally studied experimentally. In order to achieve these goals intensive joint collaboration with colleagues from chemistry and process engineering is imparative. Moreover, the applicant shall further jointly elaborate on the numerical benchmark with the other participating simulation groups, in particular providing local reaction engineering data for reactive mass transfer at Taylor bubbles using OpenFOAM.

本研究的最初目标是发展和应用一种直接数值模拟多气泡系统动态变形界面反应传质的方法。为了以可接受的计算成本解决这一多尺度问题，申请人在第一个供资期内开发了两种混合方法。在第二个资助期内，重点应放在一种专门的混合方法的应用上，以检查反应工程方面。的基本思想依赖于离散的气泡流体动力学和物种运输方程，分别为了允许更高的分辨率，特别是在浓度边界层。这种混合方法能够解决边界层中的浓度梯度，这通常变得非常陡峭的高Péclet-（雷诺数-和施密特-）和Hatta数，而两相流体动力学的解决方案的计算成本仍然是现实的。新方法的开发和应用已经使用OpenFOAM完成，OpenFOAM是计算连续介质力学的免费开源C++库。通过在优先计划的第二个资助期内使用该方法，即通过直接数值模拟，应解决两个主要方面：㈠获得关于两相流体力学、运输过程和化学反应之间复杂相互作用的详细知识和透彻理解，和（ii）分析和阐明这些过程在传质增强、液相利用以及产物分布和选择性方面的定性机理和定量影响-对于竞争性（混合敏感性）原型反应和具体测试反应，其另外通过实验研究。为了实现这些目标，与化学和工艺工程领域的同事进行深入的合作是必不可少的。此外，申请人应与其他参与模拟小组进一步共同制定数值基准，特别是使用OpenFOAM提供泰勒气泡反应传质的局部反应工程数据。