Steady three-dimensional flows past hollow fiber membrane arrays – cross flow arrangement

Abstract

Hollow fiber membrane (HFM) modules are among the most common separation devices employed in membrane separation applications. Three-dimensional steady-state computational fluid dynamics (CFD) simulations are carried out to study flow past hollow fiber membrane banks (HFMB). The current study investigates the effects of flow behavior on membrane performance during binary mixture separations. Carbon dioxide (CO2) removal from methane (CH4) is examined for various arrangements of HFMs in staggered and inline configurations. The common HFM module arrangement is the axial flow configuration. However, this work focuses on the radial cross-flow configuration. The HFM surface is a functional boundary where the suction rate and concentration of each species are coupled and are functions of the local partial pressures, the permeability, and the selectivity of the HFM. CFD simulations employed the turbulent k–ω shear stress transport (SST) model to study HFM performance for Reynolds numbers, 200 ≤ Re ≤ 1000. The efficiency of the inline and staggered arrangements in the separation module is evaluated by the coefficient of performance and the rate of mass flow per unit area of CO2 passing across the membrane surface. This work demonstrates that the module with staggered arrangement outperforms the module with the inline arrangement.

Hollow Fiber Membrane Contactors for Post-Combustion Carbon Capture: A Review of Modeling Approaches

“…Another research group investigated the effects of temperature variation on chemical reactions in a 3D HFMC bundle by directly coding the 3D energy conservation equations and RIS for heat transfer resistances [120]. There have also been studies that focus on radial variations in a bundle exposed to steady-state turbulent flow to determine the optimal fiber arrangement [121]. Although 3D bundle modeling is the most accurate and detailed approach, it is also the most computationally expensive approach mentioned so far.…”

“…Thanks to recent advances in computational ability, this is an emerging research area with room for future development. One research group has developed a 3D bundle model to study the flow passing through different fiber array arrangements for CO 2 removal from CH 4 [121]. Three-dimensional modeling is needed for this group's work to study the radial cross-flow distribution for inline and staggered fibers in the bundle, as well as momentum mixing.…”

“…In general, models should use the least number of mesh elements necessary to converge on a satisfyingly accurate solution. Examples of authors that have published their mesh study for HFMCs can be found here [64,121].…”