CFD analysis on the intensified mechanism of gas-liquid mass transfer in a microporous tube-in-tube microchannel reactor

• Published in: International journal of heat and mass transfer Vol. 182; p. 121914
• Main Authors: Li, Wen-Ling, Wang, Jian-Hong, Chen, Han, Shao, Lei, Chu, Guang-Wen, Xiang, Yang
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.01.2022; Elsevier BV
• Subjects: CFD; Coalescing; Empirical analysis; Eulerian-VOF model; Mass transfer; Mesoscale mass transfer; Microchannels; MTMCR; Multiphase; Optimization; Three dimensional models; CFD; MTMCR; Mesoscale mass transfer; Multiphase; Eulerian-VOF model
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/j.ijheatmasstransfer.2021.121914

•CFD-Eulerian model was validated with experimental data and empirical correlations.•The effects of operating conditions and structures on the mass transfer were analyzed.•The gas-liquid mass transfer mechanism in the annular microchannel was revealed.•The entrance-effect zone was determined based on the turbulent kinetic energy dissipation rate. A three-dimensional CFD model coupled with a mesoscale mass transfer model was developed to simulate the absorption of CO2 in the microporous tube-in-tube microchannel reactor (MTMCR). The simulation results were validated by experimental data and empirical correlations, with the discrepancies within ±20%. The local breakage and coalescence of the gas-liquid interfaces enhanced mass transfer in the annular microchannel. The higher ReG and ReL means lower ratio between energy for mass transfer and surface, and also, larger contribution of interfacial area to the mass transfer. Additionally, an entrance-effect zone was revealed, and the entrance-effect zone enlarged with the increase in ReG and ReL. The overall mass transfer coefficient and entrance-effect zone enlarged significantly with appropriate decrease in the length of the gas-liquid collision zone. Results of this work could provide a theoretical basis for the further optimization of MTMCR.