Slow kinetics of water escape from randomly folded foils

We study the kinetics of water escape from balls folded from square aluminum foils of different thickness and edge size. We found that the water discharge rate obeys the scaling relation Q proportional to V-P (M - M-r)(alpha) with the universal scaling exponents alpha = 3 +/- 0.1, where V-P is the volume of pore space, M(t) is the actual mass of water in the ball, and Mr is the mass of residual water. The last is found to be a power-law function of V-P. The relation of these findings to the fractal geometry of randomly folded matter is discussed.