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Title: An approach for drag correction based on the local heterogeneity for gas-solid flows

Abstract

The drag models typically used for gas-solids interaction are mainly developed based on homogeneous systems of flow passing fixed particle assembly. It has been shown that the heterogeneous structures, i.e., clusters and bubbles in fluidized beds, need to be resolved to account for their effect in the numerical simulations. Since the heterogeneity is essentially captured through the local concentration gradient in the computational cells, this study proposes a simple approach to account for the non-uniformity of solids spatial distribution inside a computational cell and its effect on the interaction between gas and solid phases. Finally, to validate this approach, the predicted drag coefficient has been compared to the results from direct numerical simulations. In addition, the need to account for this type of heterogeneity is discussed for a periodic riser flow simulation with highly resolved numerical grids and the impact of the proposed correction for drag is demonstrated.

Authors:
ORCiD logo [1];  [2];  [3];  [2];  [2]
  1. National Energy Technology Lab. (NETL), Morgantown, WV (United States); AECOM, Morgantown, WV (United States)
  2. Chinese Academy of Sciences (CAS), Beijing (China). State Key Lab. of Multiphase Complex Systems, Inst. of Process Engineering
  3. National Energy Technology Lab. (NETL), Morgantown, WV (United States)
Publication Date:
Research Org.:
National Energy Technology Lab. (NETL), Pittsburgh, PA, and Morgantown, WV (United States). In-house Research
Sponsoring Org.:
USDOE
OSTI Identifier:
1393396
Report Number(s):
CONTR-PUB-345
Journal ID: ISSN 0001-1541
Grant/Contract Number:
FE0004000
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
AIChE Journal
Additional Journal Information:
Journal Volume: 63; Journal Issue: 4; Journal ID: ISSN 0001-1541
Publisher:
American Institute of Chemical Engineers
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; computational fluid dynamics; gas–solid flow; drag model; direct numerical simulation; heterogeneous structure; sub-grid model

Citation Formats

Li, Tingwen, Wang, Limin, Rogers, William, Zhou, Guofeng, and Ge, Wei. An approach for drag correction based on the local heterogeneity for gas-solid flows. United States: N. p., 2016. Web. doi:10.1002/aic.15507.
Li, Tingwen, Wang, Limin, Rogers, William, Zhou, Guofeng, & Ge, Wei. An approach for drag correction based on the local heterogeneity for gas-solid flows. United States. doi:10.1002/aic.15507.
Li, Tingwen, Wang, Limin, Rogers, William, Zhou, Guofeng, and Ge, Wei. 2016. "An approach for drag correction based on the local heterogeneity for gas-solid flows". United States. doi:10.1002/aic.15507. https://www.osti.gov/servlets/purl/1393396.
@article{osti_1393396,
title = {An approach for drag correction based on the local heterogeneity for gas-solid flows},
author = {Li, Tingwen and Wang, Limin and Rogers, William and Zhou, Guofeng and Ge, Wei},
abstractNote = {The drag models typically used for gas-solids interaction are mainly developed based on homogeneous systems of flow passing fixed particle assembly. It has been shown that the heterogeneous structures, i.e., clusters and bubbles in fluidized beds, need to be resolved to account for their effect in the numerical simulations. Since the heterogeneity is essentially captured through the local concentration gradient in the computational cells, this study proposes a simple approach to account for the non-uniformity of solids spatial distribution inside a computational cell and its effect on the interaction between gas and solid phases. Finally, to validate this approach, the predicted drag coefficient has been compared to the results from direct numerical simulations. In addition, the need to account for this type of heterogeneity is discussed for a periodic riser flow simulation with highly resolved numerical grids and the impact of the proposed correction for drag is demonstrated.},
doi = {10.1002/aic.15507},
journal = {AIChE Journal},
number = 4,
volume = 63,
place = {United States},
year = 2016,
month = 9
}

Journal Article:
Free Publicly Available Full Text
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