Application of neutron radiography to image flow phenomena in porous media

Application of Neutron Radiography to Image Flow Phenomena in Porous Media

Neutron transmission imaging is a technique ideally suited for imaging various flow phenomena in consolidatedporous media because the porous matrix is virtually transparent to thermal neutrons. Hydrogen-containing fluids, however, provide a contrast in the image due to their large thermal neutron cross-sections. This technique has uncovered new phenomena in the study of dissolution andprecipita...

Preferential Flow Phenomena in Partially-Saturated Porous Media

Preferential flow in unsaturated porous media, in the form of fingers and channels, has been observed to take place in different types of media and at different scales. The preferential flow is caused by fluid instabilities, created by density or viscosity differences, or because of heterogeneities in the geological media. In this study, two very different types of preferential flow problems ar...

Regularized Total Variation Image Enhancement Using E.Coli Bacteria Foraging Algorithm: Application to Neutron Radiography Projections

This paper proposes a novel approach based on swarm intelligence and foraging behavior of Escherichia coli Bacteria in the human intestine for enhancing neutron radiography projections blurred during acquisition by the high neutron flux and noise contaminated due to Gamma radiations. This approach uses the total variation (TV) optimization to solve an ill-posed problem. We consider a regulariza...

Variational Image Denoising Approach with Diffusion Porous Media Flow

and Applied Analysis 3 The flow u(t) = S(t)g is a continuous semigroup of contractions in H−1(Ω) in this case or in L(Ω), in other situation, and the denoising effect of (6) is due to smoothing effect of S(t) on initial data, a property which is a characteristic to semigroups generated by the nonlinear operators A of the gradient type ∂φ, where φ is a convex and lower semicontinuous function. S...

Application of the Boundary Element Method to two Dimensional Dynamic Problems of Saturated Porous Media