Project Details
Projekt
Development and Application of a Direct Numerical Method for Reactive Transport Processes in Bubble Systems
Applicant
Dr.-Ing. Holger Marschall
Subject Area
Mathematics
Chemical and Thermal Process Engineering
Chemical and Thermal Process Engineering
Term
from 2014 to 2022
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 256677419
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.
DFG Programme
Priority Programmes
