High Resolution Neutron Imaging of Multi phase Fluid Flow through Compacted Porous Media.

In situ imaging of water flow through compacted silica sand is performed with neutron radiography and tomography at cold neutron imaging beam line CONRAD of Helmholtz Zentrum Berlin HZB , Germany. Initial microstructure of the compacted sand in dry state is obtained by using a micro focus X ray tomography system due to good contrast of silica and void phases. The flow of water is precisely controlled by using a syringe pump. Water is allowed to flow from bottom to top at a target flow rate. Time lapsed neutron radiographies are obtained during the water injection stage, followed by neutron tomography to evaluate the distribution of water, air, and silica phase in 3 D after injecting known amount of water under controlled conditions. This study has broad implications to a wide array of problems involving the use of tomography to study transport through porous material