No abstract

In this work we show through experiments, by using cohesionless granular materials, that a simple formula proposed to estimate the granular outflow from orifices in thick sidewalls is also valid for thin sidewalls. The use of such a formula entails the approximate validity of the classical Hagen and Beverloo formulas for granular samples composed of small and large grains, respectively. Also, an estimation of the involved error when the wall thickness is left aside also is given.

No abstract

Currently, very little is known about reliable phenomelogical correlations to estimate the gravity-driven mass flow rate, of dry non-cohesive granular material, outflowing from thin thickness slots in vertical sidewalls of rectangular silos. Here, we validate a simple and general formula that fits pretty well data published elsewhere, including the cases of vertically and horizontally elongated slots.

No abstract

The mass flow rate,ṁ, associated with the lateral outflow of dry, cohesionless granular material through circular orifices of diameter D made in vertical walls of silos was measured experimentally in order to determine also the influence of the wall thickness of the silo, w. Geometrical arguments, based on the outflow happening, are given in order to have a general correlation forṁ embracing both quantities, D and w. The angle of repose appears to be an important characterization factor in these kinds of flows.

No abstract

Here is studied the capillary penetration of a viscous liquid between two vertical, rectangular close together plates. In experiments the plates were joined simultaneously along two edges, and the liquid has penetrated from the bottom. Spacers with different geometries like circular, triangular and rectangular shape, were used to check their aects on the rise proles in a dynamic way, it was noticed that  when time evolves, the proles are stabilized in a catenary and the instabilities induced by efforts present in the plates disappear. Also, it is observed a rate of ascent that diers of classical values of t^1/3 or t^1/2, depending of gravity effect.