Picture of wind turbine against blue sky

Open Access research with a real impact...

The Strathprints institutional repository is a digital archive of University of Strathclyde research outputs.

The Energy Systems Research Unit (ESRU) within Strathclyde's Department of Mechanical and Aerospace Engineering is producing Open Access research that can help society deploy and optimise renewable energy systems, such as wind turbine technology.

Explore wind turbine research in Strathprints

Explore all of Strathclyde's Open Access research content

Viscous fingering of a thixotropic fluid in a porous medium or a narrow fracture

Pritchard, David (2006) Viscous fingering of a thixotropic fluid in a porous medium or a narrow fracture. Journal of Non-Newtonian Fluid Mechanics, 135. pp. 117-127. ISSN 0377-0257

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

We consider the flow of a fluid with a modified Bautista–Manero rheology injected radially into a porous medium or unidirectionally into a widening fracture. Linear stability analysis of the flows demonstrates that viscous fingering instabilities are possible, supported essentially by the thixotropic nature of the fluid: the growth rate of unstable perturbations scales approximately with the relaxation rate of the fluid, while their spatial scale is set in the radial case by where is the areal injection rate, and in the fracture case by a ‘relaxation lengthscale’ which cannot be deduced by purely dimensional reasoning. It appears likely that the same instability mechanism can occur in other shear-thinning thixotropic fluids.