CFD modeling of pressure drop and drag coefficient in fixed beds: Wall effects--颗粒学报PARTICUOLOGY

Reddy, R. K., & Joshi, J. B. (2010). CFD modeling of pressure drop and drag coefficient in fixed beds: Wall effects. Particuology, 8(1), 37–43. https://doi.org/10.1016/j.partic.2009.04.010

CFD modeling of pressure drop and drag coefficient in fixed beds: Wall effects

Rupesh K. Reddy, Jyeshtharaj B. Joshi^*

Department of Chemical Engineering, Institute of Chemical Technology, Matunga, Mumabi 400 019, India

10.1016/j.partic.2009.04.010

Volume 8, Issue 1, February 2010, Pages 37-43

Received 16 January 2009, Accepted 5 April 2009, Available online 2 October 2009.

E-mail: jbj@udct.org

Highlights

Abstract

Simulations of fixed beds having column to particle diameter ratio (D/d_p) of 3, 5 and 10 were performed in the creeping, transition and turbulent flow regimes, where Reynolds number (d_pV_Lρ_L/μ_L) was varied from 0.1 to 10,000. The deviations from Ergun's equation due to the wall effects, which are important in D/d_p < 15 beds were well explained by the CFD simulations. Thus, an increase in the pressure drop was observed due to the wall friction in the creeping flow, whereas, in turbulent regime a decrease in the pressure drop was observed due to the channeling near the wall. It was observed that, with an increase in the D/d_p ratio, the effect of wall on drag coefficient decreases and drag coefficient nearly approaches to Ergun's equation. The predicted drag coefficient values were in agreement with the experimental results reported in the literature, in creeping flow regime, whereas in turbulent flow the difference was within 10–15%.

Graphical abstract

Keywords

Computational fluid dynamics; Fixed bed; Wall effects; Pressure drop; Drag coefficient

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