HTFF 188-1 Proceedings of the 8 th World Congress on Mechanical, Chemical, and Material Engineering (MCM'22) Prague, Czech Republic – July 31, 2022 - August 02, 2022 Paper No. HTFF 188 DOI: 10.11159/htff22.188 Eulerian Approach to CFD Analysis of a Bubble Column Reactor – A Review Mohammed W. Abdulrahman, Nibras Nassar Rochester Institute of Technology Dubai, UAE mwacad@rit.edu; nin8507@rit.edu Abstract - Bubble Column Reactors (BCR) / Slurry Bubble Column Reactors (SBCR) have many advantageous characteristics as such they are used in numerous industrial applications. This work reviews the Eulerian Computational Fluid Dynamics (CFD) approach when analysing BCR/ SBCRs. Several studies have been reviewed which vary parameters such as the reactor design, superficial gas velocity, pressure, CFD models (drag, turbulence), particle concentration, and phase material to investigate their effects on the reactor’s performance in terms of hydrodynamics or heat transfer. This review indicates that using a Eulerian CFD model can accurately predict the BCR/SBCR’s performance. Key findings include that increasing the superficial gas velocity, column pressure, and gas phase density increases the gas holdup. Gas holdup is unevenly distributed in the BCR where most of the gas holdup is in the centre of the column. Increasing solid particles decreases the bubble breakup rate and gas holdup. Furthermore, it was concluded that increasing the superficial gas velocity increases the average slurry temperature and volumetric heat transfer. However, decreasing the column height increases the slurry temperature and volumetric heat transfer. Keywords: CFD; bubble columns; hydrodynamics; heat transfer; Eulerian 1. Introduction Bubble column reactors are multiphase vertical reactors which contain a gas, a liquid or slurry, and fine particles where the gas is fed into the reactor by a sparger where bubbles are formed inside the liquid/ slurry. BCR/SBCR are advantageous as they can be used in a variety of industrial applications. Furthermore, the liquid in the three-phase reaction is beneficial as it allows for a more precise temperature control due to the liquid’s high heat capacity [1]. Scaling up, modelling, and designing slurry bubble column reactors is a complex process as it requires detailed knowledge in relation to kinetics, hydrodynamics, heat and mass transfer, chemical reaction rates, phase holdup, flow regimes, pressure change, and solid distribution. CFD simulations can be used to help model the reactions and design the reactors. When studying BCR/SBCR it is important to focus on the gas holdup as it is one of the most important characteristics of the BCR [2]. Over the years research has been conducted in relation to bubble column reactors both experimentally and by means of CFD software. Research conducted has investigated theeffects of gas holdup, coalescence, reactor dimension, operational pressure, and heat transfer onthe reactions. This review will aid in future development and design of BCR/SBCRs by highlighting the CFD findings of previous studies. 2. Hydrodynamic Investigations of BCR/ SBCR Meier et al. [3] conducted a 3D CFD investigation of a gas-liquid flow in a churn turbulent regime in order to compare the effectiveness of several models in relation to predicting the drag closures, breakup, and coalescence. Twelve combinations of the breakup and coalescence models were created and simulated. The combinations included a mixture of the breakage closures and coalescence closures. The Breakage closures used by Luo and Svendsen [4], Lehr et al. [5], and Laakkonen et al. [6] with Generalized PDF distribution. The coalescence closures used were Prince and Blanch [7], Luo [8] and Das [9]. Once simulated the CFD models were compared to the experimental data of Manjrekar and Dudukovic [10]. The Manjrekar and Dudukovic [10] bubble column reactor has a cylindrical diameter of 20.32 cm and a height of 2m. Experiments were carried out on the combination of 12 models with air-water flows at superficial gas velocities of 20 cm/s and 40 cm/s. The results highlighted the importance of selecting the appropriate breakage and coalescence closure model. In particular the breakup model, as the breakup model had a larger impact on the flow prediction than the coalescence