Please use this identifier to cite or link to this item: https://doi.org/10.1016/S0009-2509(98)00193-6
Title: Transient development of instabilities in bounded shear flow of granular materials
Authors: Wang, C.-H. 
Tong, Z.
Keywords: FFT
Flow
Granular material
Instability
Power spectra
Transient development
Issue Date: Nov-1998
Source: Wang, C.-H., Tong, Z. (1998-11). Transient development of instabilities in bounded shear flow of granular materials. Chemical Engineering Science 53 (22) : 3803-3819. ScholarBank@NUS Repository. https://doi.org/10.1016/S0009-2509(98)00193-6
Abstract: A study has been conducted on the analysis and fate of instabilities arising from rapid shear flow of a granular material. Specifically, this study is made through a detailed analysis of continuum rheological models, to examine whether the initiation and growth of the instabilities predicted by this analysis are consistent with the linear stability theory. It is found that rapidly sheared particles tend to form alternating bands or clusters of high and low solid concentrations. Two types of standing-wave instabilities, namely layering and stationary modes, are investigated. The fate of these density waves is tracked through transient integration of the macroscopic balance equations, and examined by a fast Fourier transform (FFT) analysis. In such a formulation, a few characteristic modes with different wave numbers have been identified. The temporal evolution of the intensity of fluctuating energy is investigated by analyzing the most dominant mode in the system. It is found that the structure and dynamics of the resulting waves can be quantitatively correlated with the power spectrum density of concentration fluctuations. The development of the layering mode is governed primarily by linear instability. On the other hand, clusters of particles of the stationary mode may stretch and interact with neighboring clusters. This new finding indicates that the transient development of a two-dimensional stationary disturbance may ultimately lead to a one-dimensional layered structure. The stationary and layering perturbations eventually evolve to a similar structure and the stationary perturbation leads the system to the layered state more rapidly than the layering mode.
Source Title: Chemical Engineering Science
URI: http://scholarbank.nus.edu.sg/handle/10635/67590
ISSN: 00092509
DOI: 10.1016/S0009-2509(98)00193-6
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.

SCOPUSTM   
Citations

9
checked on Dec 14, 2017

WEB OF SCIENCETM
Citations

9
checked on Nov 19, 2017

Page view(s)

33
checked on Dec 10, 2017

Google ScholarTM

Check

Altmetric


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.