UPM Institutional Repository

On the onset of incipient fluidization


Citation

Tan, Ka Kheng and Tan, Yee Wan and Tey, Beng Ti and Look, Kar Yang (2008) On the onset of incipient fluidization. Powder Technology, 187 (2). pp. 175-180. ISSN 0032-5910; ESSN: 1873-328X

Abstract

The onset of incipient fluidization is investigated theoretically and simulated by a computational fluid dynamics (CFD) procedure. The onset of incipient instability in a particle bed is preceded by stable gas diffusion in the interstices and is caused by a critical momentum force that may overcome the inertia of the particles. The critical momentum force is provided by the critical superficial gas velocity Uc in the form of critical mass flux of diffusion. It is found that the first movement of particles may be predicted by a critical transient Rayleigh number determined by a critical superficial velocity equals to the minimum fluidization velocity, Umf. The onset of incipient fluidization was found to occur at a critical transient Rayleigh number of 3.1, which is close to the lowest theoretical value for buoyancy convection in a porous medium bounded by free surfaces. Consequently the onset times of incipient fluidization may be predicted accurately. The finding has been found to be supported by the present CFD study, past experiments and simulations in the literature.


Download File

[img]
Preview
PDF (Abstract)
On the onset of incipient fluidization.pdf

Download (83kB) | Preview

Additional Metadata

Item Type: Article
Divisions: Faculty of Engineering
DOI Number: https://doi.org/10.1016/j.powtec.2008.02.008
Publisher: Elsevier
Keywords: Onset; Incipient fluidization; Transient Rayleigh number
Depositing User: Fatimah Zahrah @ Aishah Amran
Date Deposited: 10 Nov 2014 03:57
Last Modified: 30 Nov 2016 03:36
Altmetrics: http://www.altmetric.com/details.php?domain=psasir.upm.edu.my&doi=10.1016/j.powtec.2008.02.008
URI: http://psasir.upm.edu.my/id/eprint/15922
Statistic Details: View Download Statistic

Actions (login required)

View Item View Item