Fluidization of wet granular matter

We have studied the effect of small amounts of added liquid on the dynamic behavior of a granular system consisting of spherical glass beads. The critical acceleration $\Gamma$ for fluidization is found to increase strongly when liquid is added. It furthermore depends on the bead radius, the height of the sample, and the shaking frequency. As our main result, we find that these dependencies can be presented in a factorized form. We present a simple model which accounts for most of our findings.