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Published on: December 4, 2017
Porous agglomerates in the general linear flow field
1Laboratory of Transport Processes in Porous Materials, Faculty of Mechanical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.
Journal of Colloid and Interface Science
|January 3, 2006
Summary
This study models fluid flow in and around porous spherical particles using Stokes and Brinkman equations. It introduces a method to calculate suspension viscosity, generalizing Einstein
Area of Science:
- Fluid Dynamics
- Rheology
- Particle Science
Background:
- Understanding fluid flow around porous particles is crucial for various applications.
- Existing models often simplify particle behavior, neglecting internal flow dynamics.
- The Brinkman equation extends Darcy's law to describe flow within porous media.
Purpose of the Study:
- To calculate the flow field within and around porous spherical agglomerates.
- To determine the effective viscosity of dilute suspensions of these porous aggregates.
- To generalize Einstein's equation for solid suspensions to include porous particles.
Main Methods:
- Utilized Stokes equations for flow exterior to the particle.
- Employed Brinkman equations for flow inside the porous particle.
- Defined the Brinkman parameter (beta) to quantify particle permeability's effect.
Main Results:
- Developed solutions for the flow field of porous spherical agglomerates in linear flow.
- Calculated the effective viscosity of dilute suspensions of porous aggregates.
- Proposed an agglomerate effective viscosity diameter for viscosity calculations.
Conclusions:
- The study provides a framework for analyzing porous particle dynamics in creeping shear flows.
- The generalized Einstein's equation offers a new way to evaluate suspension viscosity.
- This work enhances the understanding of rheological properties of porous material suspensions.
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