Paste flow in porous systems

Using the free open access in the Mini 0.75/ MiniWB57R MR-Microscopy probe a flow experiment setup was placed inside the probe and inserted into a Bruker widebore system. Multi layer pastes with different water content, were pushed into a tube while the flow at the piston outlet was examined using standard MR microcopy techniques. Depending on the water content, different flow behavior were monitored at the piston outlet, which is depicted in figure 1 for two pasts with a water content of 74% and 76% of water.

With the help of localized spectroscopy, the separation of the paste, due to experiment parameters, such as pressure and temperature gradients, can be determined and tracked over the whole sample area. 

MR Microcopy hard- and software provides the user with a powerful tool to resolve sample dimensions far smaller than standard MR imaging, which is of great interest if looking at flow in porous systems. If a conglomeration of particles in a porous system as depicted in figure 2 cannot be resolved the flow is averaged over this region and information is lost. MR microscopy systems, depending on the set-up, enable to resolve objects in the range of several tens of micrometers.

References: 

Götz, J., Kreibich, W., Peciar, M. and Buggisch, H., 2001. MRI of Couette experiments in a newly developed shear device—suitable for pastes and concentrated suspensions?. Journal of non-newtonian fluid mechanics, 98(2-3), pp.117-139.