Transport Properties in Sheared Granular Flows

2002 ◽  
Author(s):  
Shu-San Hsiau
Keyword(s):  
The Self ◽  
Shear Stresses ◽  
Streamwise Direction ◽  
Shear Cell ◽  
Self Diffusion ◽  
Particle Tracking Method ◽  
Glass Spheres ◽  
The Mean ◽  
Self Diffusion Coefficient ◽  
Normal And Shear Stresses

This paper tends to review the experiments performed in a shear cell device at National Central University. The influences of wall conditions and particle solid fractions were investigated. The glass spheres with a mean diameter of 3 mm were used as granular materials. Three bi-directional stress gages were installed to measure the normal and shear stresses along the upper wall. The image processing technology and particle tracking method were employed to measure the average and fluctuation velocities in the streamwise and the transverse directions. By tracking the movements of particles continually, the variation in the mean-square diffusive displacements with time was plotted and the self-diffusion coefficient was determined. The self-diffusion coefficients in the streamwise direction were much higher than those in the transverse direction. Besides the fundamental observations in a shear device, this paper will briefly describe the technology of “moving granular bed filter” developed at National Central University. This technology is mainly developed for high temperature gas cleanup.

scholarly journals Self-Diffusion and Transport Mechanisms in Cubic Lithium Sulphate

1967 ◽  
Vol 22 (2) ◽  
pp. 213-214 ◽  
Author(s):  
Arnold Kvist ◽  
Ulf Trolle
Keyword(s):  
Electrical Conductivity ◽  
Diffusion Coefficient ◽  
Lithium Ion ◽  
Mean Value ◽  
The Self ◽  
Transport Mechanisms ◽  
Self Diffusion ◽  
Lithium Sulphate ◽  
The Mean ◽  
Self Diffusion Coefficient

The self-diffusion coefficient of the lithium ion in cubic lithium sulphate has been measured from 640 to 790°C. From electrical conductivity and electromigration experiments it has been found that several cations are moving in phase and the mean value of the number of ions in each group has been estimated to be about 2.0. The measurements of the self-diffusion coefficient indicate that we also have transport mechanisms, which contribute more to the diffusion than to the electrical conduction.

Self-diffusion of Tin in a liquid Tin-Lead alloy at the Eutectic Composition

1976 ◽  
Vol 31 (8) ◽  
pp. 1024 ◽  
Author(s):  
D. H. Kurlat ◽  
M. Rosen ◽  
G. Quintana
Keyword(s):  
Diffusion Coefficient ◽  
Eutectic Composition ◽  
The Self ◽  
Lead Alloy ◽  
Shear Cell ◽  
Temperature Range ◽  
Self Diffusion ◽  
Cluster Hypothesis ◽  
Liquid Tin ◽  
Self Diffusion Coefficient

Abstract By the shear cell technique, the self-diffusion coefficient (DSn) of tin in a liquid Sn - 38.1 wt% Pb alloy has been measured in the temperature range 466 to 786 K. The slope of the DSn vs. T curve decreases up to about 573 K, where it gets constant. This behaviour may be explained by the cluster hypothesis.

Investigation on the Diffusion Behavior of Mo-Ni Interface

2010 ◽  
Vol 152-153 ◽  
pp. 1607-1610 ◽  
Author(s):  
Wei Chan Cao ◽  
Shu Hua Liang ◽  
Yue Xin Xue ◽  
Xian Hui Wang
Keyword(s):  
Solid Solution ◽  
Diffusion Coefficient ◽  
Electron Microscope ◽  
Intermetallic Compound ◽  
Diffusion Layer ◽  
Interdiffusion Coefficient ◽  
The Self ◽  
Diffusion Behavior ◽  
Self Diffusion ◽  
Self Diffusion Coefficient

In order to gain a deep insight into the mechanism of Ni-doped Mo activated sintering process, the diffusion behavior of Mo-Ni interface was studied utilizing a Mo-Ni diffusion couple. The phase structure and composition on the diffusion layer were characterized and analyzed by means of scanning electron microscope and transmission electron microscope, the self diffusion coefficient and interdiffusion coefficient were calculated. The results show that a diffusion layer is formed between Mo and Ni after sintering at 1223k for 1h, which is comprised of a δ-NiMo intermetallic compound and a limit solid solution containing small amounts of nickel. The self diffusion coefficient and interdiffusion coefficient are 2.068×10-18cm2/s and 4.5×10-12cm2/s, respectively. It is suggested that the diffusion rate of Mo in δ-NiMo intermetallic compound and a limit solid solution containing small amounts of nickel is 106 times bigger than that of self diffusion, and the intermetallic compound layer provides a short diffusion path for Mo activated sintering.

Self-Diffusion in Molten Lithium Nitrate

1992 ◽  
Vol 47 (10) ◽  
pp. 1047-1050 ◽  
Author(s):  
C. Herdlicka ◽  
J. Richter ◽  
M. D. Zeidler
Keyword(s):  
Diffusion Coefficient ◽  
Diffusion Coefficients ◽  
Spin Echo ◽  
The Self ◽  
Lithium Nitrate ◽  
Equimolar Ratio ◽  
Self Diffusion ◽  
Field Gradients ◽  
Molten Lithium ◽  
Self Diffusion Coefficient

AbstractSelf-diffusion coefficients of 7Li+ ions have been measured in molten LiNO3 with several compositions of 6Li+ and 7Li+ over a temperature range from 537 to 615 K. The NMR spin-echo method with pulsed field gradients was applied. It was found that the self-diffusion coefficient depends on the isotopic composition and shows a maximum at equimolar ratio. At temperatures above 600 K this behaviour disappears.

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