Non-isothermal analysis of concentrated suspension slip flow with particle migration

2008 ◽  
Vol 68 (2) ◽  
pp. 398-409 ◽  
Author(s):  
Xing Chen ◽  
Yee Cheong Lam ◽  
Zhiying Wang
Keyword(s):  
Slip Flow ◽  
Particle Migration ◽  
Concentrated Suspension ◽  
Isothermal Analysis

Heat transfer and shear-induced migration in dense non-Brownian suspension flows: modelling and simulation

2018 ◽  
Vol 840 ◽  
pp. 432-454 ◽  
Author(s):  
T. Dbouk
Keyword(s):  
Heat Transfer ◽  
Thermal Diffusivity ◽  
Shear Rate ◽  
Volume Fraction ◽  
Particle Volume Fraction ◽  
Laminar Flows ◽  
Modelling And Simulation ◽  
Particle Migration ◽  
Concentrated Suspension ◽  
Suspension Flows

Modelling and simulation are developed, generalized and validated for both heat transfer and shear-induced particle migration in dense non-colloidal laminar suspension flows. Past theory and measurements for the effective thermal conductivity in porous materials at zero shear rate are coupled to more recent effective thermal diffusivity measurements of sheared suspensions. The suspension effective heat transfer affected by the local shear rate ($\dot{\unicode[STIX]{x1D6FE}}$), the phenomenon of shear-induced particle migration (SIM), the buoyancy effects ($\unicode[STIX]{x0394}\unicode[STIX]{x1D70C}$) and the thermal Péclet number ($Pe_{d_{p}}=\dot{\unicode[STIX]{x1D6FE}}d_{p}^{2}/\unicode[STIX]{x1D6FC}_{f}$, where $d_{p}$ is the diameter of rigid particles and $\unicode[STIX]{x1D6FC}_{f}$ is the fluid phase thermal diffusivity) at the particle scale are all considered in the present constitutive three-dimensional modelling. Moreover, the influence of the temperature, the shear rate and the particle volume fraction ($\unicode[STIX]{x1D719}$) on the suspension effective viscosity ($\unicode[STIX]{x1D702}_{S}$), the suspension effective thermal properties and the fluid density ($\unicode[STIX]{x1D70C}_{f}$) are taken also into account. The present contribution represents an emerging field of heat transfer applications of complex fluid flows and is very beneficial for many future applications where concentrated suspension laminar flows with conjugate heat transfer may be present (e.g. for designing more innovative and compact heat exchangers).

Shear-induced particle migration in a polydisperse concentrated suspension

1998 ◽  
Vol 42 (6) ◽  
pp. 1329-1348 ◽  
Author(s):  
Anat Shauly ◽  
Amir Wachs ◽  
Avinoam Nir
Keyword(s):  
Particle Migration ◽  
Concentrated Suspension

Particle migration in a concentrated suspension flowing between rotating parallel plates: Investigation of diffusion flux coefficients

2005 ◽  
Vol 49 (6) ◽  
pp. 1429-1448 ◽  
Author(s):  
Dima Merhi ◽  
Elisabeth Lemaire ◽  
Georges Bossis ◽  
Fadl Moukalled
Keyword(s):  
Diffusion Flux ◽  
Particle Migration ◽  
Parallel Plates ◽  
Concentrated Suspension

scholarly journals Hydrodynamic particle migration in a concentrated suspension undergoing flow between rotating eccentric cylinders

1995 ◽  
Vol 34 (10) ◽  
pp. 3187-3194 ◽  
Author(s):  
Nhan Phan-Thien ◽  
Alan L. Graham ◽  
Stephen A. Altobelli ◽  
James R. Abbott ◽  
Lisa A. Mondy
Keyword(s):  
Particle Migration ◽  
Concentrated Suspension ◽  
Eccentric Cylinders

Simulation of Particle Migration of Powder-Resin System in Injection Molding

2003 ◽  
Vol 125 (3) ◽  
pp. 538-547 ◽  
Author(s):  
Y. C. Lam ◽  
X. Chen ◽  
K. C. Tam ◽  
S. C. M. Yu
Keyword(s):  
Injection Molding ◽  
Concentration Distribution ◽  
Powder Injection Molding ◽  
Particle Migration ◽  
Powder Injection ◽  
Powder Concentration ◽  
Powder Density ◽  
Isothermal Analysis ◽  
Filling Phase ◽  
Important Processing

Powder injection molding is an important processing method for producing precision metallic or ceramic parts. Experience, intuition and trial-and-error have been the practice for the design and process optimization of such molding operations. However, this practice is becoming increasingly inefficient and impractical for the molding of larger, more complicated and more costly parts. In this investigation, a numerical method for simulating the mold-filling phase of powder injection molding was developed. The flow was modelled using the Hele-Shaw approach coupled with particle diffusion transport equation for the calculation of powder concentration distribution. The viscosity of the feedstock was evaluated using a power-law type rheological model to account for the viscosity dependency on shear rate and powder concentration. A numerical example is presented and discussed to demonstrate the capabilities and limitations of the simulation algorithm, which has the potential as an analytical tool for the mold designer. The variation of powder density distribution can be predicted, which is ignored by the existing simulation packages. Preliminary simulation indicated that powder concentration variation could be significant. Non-isothermal analysis indicated that most of the key parameters for filling process would change due to a change in powder concentration distribution.

An experimental investigation of concentrated suspension flows in a rectangular channel

1994 ◽  
Vol 266 ◽  
pp. 1-32 ◽  
Author(s):  
Christopher J. Koh ◽  
Philip Hookham ◽  
L. G. Leal
Keyword(s):  
Volume Fraction ◽  
Laser Doppler Anemometry ◽  
Rectangular Channel ◽  
Particle Migration ◽  
Refractive Indices ◽  
Concentrated Suspension ◽  
Suspension Flows ◽  
Liquid Phases ◽  
Scattering Volume ◽  
Optical Turbidity

An experimental adaptation of the well-known laser-Doppler anemometry technique is developed for measuring the velocity and concentration profiles in concentrated suspension flows. To circumvent the problem of optical turbidity, the refractive indices of the solid and liquid phases are closely matched. The residual turbidity, owing to small mismatches of the refractive indices, as well as impurities in the particles, allows a Doppler signal to be detected when a particle passes through the scattering volume. By counting the number of Doppler signals in a period of time, the local volume fraction is also measured.This new technique is utilized to study concentrated suspension flows in a rectangular channel. The general behavior of the suspension is that the velocity profile is blunted while the concentration profile has a maximum near the centre. Comparisons are made with theoretical predictions based on the shear-induced particle migration theory.

Particle migration of concentrated suspension flow in bifurcating channels

2019 ◽  
Vol 30 (9) ◽  
pp. 1897-1909
Author(s):  
Bhaskar Jyoti Medhi ◽  
Mallela Mallikarjuna Reddy ◽  
Anugrah Singh
Keyword(s):  
Particle Migration ◽  
Suspension Flow ◽  
Concentrated Suspension

Shear-Induced Size Segregation Phenomena in Bidisperse Suspensions

1994 ◽  
Vol 47 (6S) ◽  
pp. S236-S239 ◽  
Author(s):  
Gokul P. Krishnan ◽  
David T. Leighton
Keyword(s):  
Reynolds Number ◽  
Parallel Plate ◽  
Migration Velocity ◽  
Particle Migration ◽  
Size Segregation ◽  
Concentrated Suspension ◽  
Colloidal Spheres ◽  
Tracer Particles ◽  
Flow Geometry ◽  
Wide Gap

The behavior of tracer particles in a concentrated suspension of non-colloidal spheres sheared in a parallel plate viscometer at low Reynolds number was investigated. The tracer particles were shown to migrate radially, with the tracer particles larger than those making up the suspension migrating radially outward. The migration velocity of the large tracer particles was measured, and found to be consistent with a shear-induced migration scaling (Leighton and Acrivos, 1987b), however the direction of the migration was the reverse of that suggested by the experiments of Abbot, et al. (1991) in a wide gap Couette device. The particle migration and segregation described here are interpreted in terms of the curvature of the flow geometry.

Sign in / Sign up

Export Citation Format

Share Document