Development of a filtered reaction rate model for reactive gas–solid flows based on fine‐grid simulations. Issue 5 (29th January 2021)

• Record Type: Journal Article
• Authors: Huang, Zheqing; Wang, Lingxue; Zhou, Qiang
• Is Part Of: AIChE journal. Volume 67:Issue 5(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-01-29
• Subjects: fine‐grid simulation -- fluidization -- mesoscale effectiveness factor -- reactive gas–solid flow -- two‐fluid model; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; 660.28
• DOI: 10.1002/aic.17185
• Languages: English
• ISSNs: 0001-1541

Abstract

Abstract: The filtered reaction rate for the coarse‐grid simulations of reactive gas–solid flows can be obtained via a correction to its microscopic reaction rate. The correction term is defined as the mesoscale effectiveness factor η Δ, which is the ratio of the reaction rate obtained from the fine‐grid simulations to that obtained from the coarse‐grid simulations. The considered reaction is an isothermal, solid‐catalyzed surface reaction with a power law reaction rate model. The simulation results show that the mean η Δ is almost invariant with the reaction orders at the same Damköhler number. A closure correlation for the mean η Δ is formulated. However, the standard deviation of η Δ is found to be quite large. A presumed probability density function model is proposed to capture the fluctuating properties of η Δ . The predictability of the closure correlations are evaluated via performing the filtered two fluid model simulations in circulating fluidized beds of ozone decomposition.