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Title: An efficient and reliable predictive method for fluidized bed simulation

Abstract

In past decades, the continuum approach was the only practical technique to simulate large-scale fluidized bed reactors because discrete approaches suffer from the cost of tracking huge numbers of particles and their collisions. This study significantly improved the computation speed of discrete particle methods in two steps: First, the time-driven hard-sphere (TDHS) algorithm with a larger time-step is proposed allowing a speedup of 20-60 times; second, the number of tracked particles is reduced by adopting the coarse-graining technique gaining an additional 2-3 orders of magnitude speedup of the simulations. A new velocity correction term was introduced and validated in TDHS to solve the over-packing issue in dense granular flow. The TDHS was then coupled with the coarse-graining technique to simulate a pilot-scale riser. The simulation results compared well with experiment data and proved that this new approach can be used for efficient and reliable simulations of large-scale fluidized bed systems.

Authors:
ORCiD logo [1];  [1];  [2]
  1. National Energy Technology Lab. (NETL), Morgantown, WV (United States)
  2. National Energy Technology Lab. (NETL), Morgantown, WV (United States); AECOM, 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:
1402453
Report Number(s):
NETL-PUB-20967
Journal ID: ISSN 0001-1541
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
AIChE Journal
Additional Journal Information:
Journal Volume: 63; Journal Issue: 12; Journal ID: ISSN 0001-1541
Publisher:
American Institute of Chemical Engineers
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; 97 MATHEMATICS AND COMPUTING; discrete particle model, particle in cell, hard sphere collision, fluidization

Citation Formats

Lu, Liqiang, Benyahia, Sofiane, and Li, Tingwen. An efficient and reliable predictive method for fluidized bed simulation. United States: N. p., 2017. Web. doi:10.1002/aic.15832.
Lu, Liqiang, Benyahia, Sofiane, & Li, Tingwen. An efficient and reliable predictive method for fluidized bed simulation. United States. doi:10.1002/aic.15832.
Lu, Liqiang, Benyahia, Sofiane, and Li, Tingwen. 2017. "An efficient and reliable predictive method for fluidized bed simulation". United States. doi:10.1002/aic.15832.
@article{osti_1402453,
title = {An efficient and reliable predictive method for fluidized bed simulation},
author = {Lu, Liqiang and Benyahia, Sofiane and Li, Tingwen},
abstractNote = {In past decades, the continuum approach was the only practical technique to simulate large-scale fluidized bed reactors because discrete approaches suffer from the cost of tracking huge numbers of particles and their collisions. This study significantly improved the computation speed of discrete particle methods in two steps: First, the time-driven hard-sphere (TDHS) algorithm with a larger time-step is proposed allowing a speedup of 20-60 times; second, the number of tracked particles is reduced by adopting the coarse-graining technique gaining an additional 2-3 orders of magnitude speedup of the simulations. A new velocity correction term was introduced and validated in TDHS to solve the over-packing issue in dense granular flow. The TDHS was then coupled with the coarse-graining technique to simulate a pilot-scale riser. The simulation results compared well with experiment data and proved that this new approach can be used for efficient and reliable simulations of large-scale fluidized bed systems.},
doi = {10.1002/aic.15832},
journal = {AIChE Journal},
number = 12,
volume = 63,
place = {United States},
year = 2017,
month = 6
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on June 29, 2018
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