Computational fluid dynamics bubble size

FIGURE 4.1 Application of computational fluid dynamics to simulate (A) bubble position after 120 s during O2 dosage at 26 mg/L/month and 670- tm bubble size (B) represents a diagonal slice of the wine phase velocity field, and (C) the dissolved oxygen concentration in milligram per liter. Reprinted with permission from Dykes and Kilmartin (2007). Copyright 2007 Winetitles Pty Ltd. 

Slurry bubble column reactor for methanol and other hydrocarbons productions from synthesis gas is an issue of interest to the energy industries throughout the world. Computational fluid dynamics (CFD) is a recently developed tool which can help in the scale up. We have developed an algorithm for computing the optimum process of fluidized bed reactors. The mathematical technique can be applied to gas solid, liquid-solid, and gas-liquid-solid fluidized bed reactors, as well as the LaPorte slurry bubble column reactor. Our computations for the optimum particle size show that there is a factor of about two differences between 20 and 60 pm size with maximum granular-like temperature (turbulent kinetic energy) near the 60 pm size particles. 

Bubble (and slug) lengths have been obtained experimentally or through computational fluid dynamic simulations [28-30]. These revealed that sizes are mainly affected by gas and liquid superficial velocities and contactor size and slightly by... 

Gas-liquid mixed tanks are used for various operations in industrial practise. The design of gas-liquid mixing units and reactors is still done by empirical correlations, which are usually valid for specific components, mixing conditions and geometries. Computational Fluid Dynamic (CFD) techniques have been used successfully for single-phase flow, but gas-liquid flow calculations are still tedious for computers. Therefore, simpler and more accurate multiphase models are needed. In order to verify multiphase CFD calculations and to fit unknown parameters in the multiphase models, experimental local bubble size distributions and flow patterns are needed. 

ChenJ, Yang N, Ge W, et al Computational fluid dynamics simulation of regime transition in bubble columns incorporating the dual-bubble-size model, Ind Eng Chem Res 48 8172-8179, 2009b. 

---