AGGREGATION AND DISPERSION OF SPHERES FALLING IN VISCOELASTIC LIQUIDS

被引:139
作者
JOSEPH, DD
LIU, YJ
POLETTO, M
FENG, J
机构
[1] Department of Aerospace Engineering and Mechanics, University of Minnesota, Minneapolis, MN 55455, 107 Akerman Hall
基金
美国国家科学基金会;
关键词
AGGREGATION OF SPHERES; DISPERSION OF SPHERES; ELASTIC STRESS RATIO; NEWTONIAN LIQUIDS; NUMERICAL SIMULATION; SETTLING OF SPHERES; SPHERE SPHERE INTERACTION; VISCOELASTIC LIQUIDS; WALL SPHERE INTERACTION;
D O I
10.1016/0377-0257(94)80015-4
中图分类号
O3 [力学];
学科分类号
08 ; 0801 ;
摘要
This paper focuses on the settling on one sphere near another or near a wall. We find maximum differences between Newtonian and viscoelastic liquids, with repulsion between nearby bodies in the Newtonian case and attraction in the viscoelastic case. Side-by-side arrangements of sedimenting spheres are unstable in exactly the same way that broadside-on settling of long bodies is unstable at subcritical speeds in a viscoelastic fluid. The line of centers between the spheres rotates from across to along the stream as the spheres are sucked together. The resulting chain of two spheres is a long body which is stable when the line between centers is parallel to the fall, but this configuration breaks up at subcritical speeds where inertia again dominates. To explain the orientation of particles in the supercritical case, we correlate the aggregative power of a viscoelastic fluid with a zero shear value of the coefficient of ratio of the first normal stress difference to the shear stress and for exceptional cases we introduce the idea of the memory of shear-thinning leading to corridors of reduced viscosity.
引用
收藏
页码:45 / 86
页数:42
相关论文
共 32 条
[1]  
Barnes H.A., 1989, INTRO RHEOLOGY, V3
[2]   ROTATING ROD VISCOMETER [J].
BEAVERS, GS ;
JOSEPH, DD .
JOURNAL OF FLUID MECHANICS, 1975, 69 (JUN10) :475-&
[3]  
Bird R. B., 1987, DYNAMICS POLYM LIQUI
[4]   SLOW MOTION OF A RIGID PARTICLE IN A 2ND-ORDER FLUID [J].
BRUNN, P .
JOURNAL OF FLUID MECHANICS, 1977, 82 (SEP27) :529-547
[5]  
Bungay PM, 1973, INT J MULTIPHAS FLOW, V1, P25, DOI DOI 10.1016/0301-9322(73)90003-7
[7]   NON-NEWTONIAN VISCOSITY MEASUREMENTS IN THE INTERMEDIATE SHEAR RATE RANGE WITH THE FALLING-BALL VISCOMETER [J].
CHO, YI ;
HARTNETT, JP ;
LEE, WY .
JOURNAL OF NON-NEWTONIAN FLUID MECHANICS, 1984, 15 (01) :61-74
[8]  
CHO YI, 1979, J HEAT MASS TRANSFER, V6, P335
[9]   AN EXAMPLE OF MINIMUM ENERGY DISSIPATION IN VISCOUS FLOW [J].
CHRISTOPHERSON, DG ;
DOWSON, D .
PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL AND PHYSICAL SCIENCES, 1959, 251 (1267) :550-564
[10]   DIRECT SIMULATION OF INITIAL-VALUE PROBLEMS FOR THE MOTION OF SOLID BODIES IN A NEWTONIAN FLUID .1. SEDIMENTATION [J].
FENG, J ;
HU, HH ;
JOSEPH, DD .
JOURNAL OF FLUID MECHANICS, 1994, 261 :95-134