An Eulerian‐Eulerian Computational Approach for Simulating Descending Gas‐Liquid Flows in Reactors with Solid Foam Internals

Abstract

Dedicated to Professor Rüdiger Lange on the occasion of his 65th birthdayChemical reactors with new types of packings, such as metallic and ceramic openpore foams, have become subjects of scientific and engineering interest in the past decades. For trickle bed reactors, the new packing types provide favorable conditions, such as high specific surface area and low pressure drop, which are believed to contribute to an intensification of mass and heat transfer. Here, an attempt was made to model and predict the flow pattern and liquid distribution in a trickle bed reactor with solid foams, using computational fluid dynamics. A three-dimensional model based on the relative permeability approach was adopted, where gas and liquid phases flow co-currently downwards through a reactor with SiSiC ceramic foams as internals. The influence of both mechanical and capillary dispersion was included and studied in detail for foams of two different pore densities and for different initial distribution patterns.

Reaktoren für Dreiphasen-Reaktionen: Rieselbettreaktoren

“…Das Phasenverteilungsvermögen von keramischen Feststoffschäumen als Alternative zu regellosen Katalysatorschüttungen (siehe Kap. ▶ "Reaktoren für Dreiphasen-Reaktionen: Monolithreaktoren") wurde von Subramanian et al (2017) mittels CFD untersucht. Dashliborun und Larachi (2019) untersuchten jüngst den Einfluss von Wellenbewegungen auf die Hydrodynamik bei Offshore-Anwendungen von Rieselbettreaktoren.…”

Eulerian Multi-Fluid Model for Polydisperse Flows

“…The third approach is the Eulerian approach, where all phases are described in the Eulerian frame of reference. All phases are described as interpenetrating continua [6,7,8], and method is suitable for a broad spectrum of various flow regimes.…”

Implicitly coupled phase fraction equations for polydisperse flows

“…that is, when the dispersed phase fraction is low 7,8 . The Eulerian approach describes all phases in the Eulerian frame of reference, and all phases are treated as interpenetrating continua 9‐11 . This approach is suitable for a wide range of different flow regimes.…”