Origin of stability in sedimentation -: art. no. 254503

被引：11

作者：

Segrè, PN ^{[1
]}

机构：

[1] NASA, George C Marshall Space Flight Ctr, Biophys Grp, Huntsville, AL 35812 USA

来源：

PHYSICAL REVIEW LETTERS | 2002年 / 89卷 / 25期

关键词：

D O I：

10.1103/PhysRevLett.89.254503

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Velocity fluctuations and particle concentrations are studied in a liquid fluidized bed to investigate the origin of steady state sedimentation. Both the velocity fluctuations and the particle concentrations are found to strongly depend on height. A flux balance model shows why the bed is stable: velocity fluctuations drive a downward particle flux that is compensated by an upward particle flux stemming from an excess flow velocity due to the stratification in concentration. Our results show that in steady state the magnitudes of the fluctuations are related to the degree of stratification.

引用

页数：4

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