The S-valve: Modeling granular solids flow using dimensionless numbers [La válvula-S: Modelado del flujo de sólidos granulares utilizando números adimensionales]

Abstract

In this work, Pi-Buckingham Method of Dimensional Analysis was used to obtain a simple mathematical model to predict flow of solids from a novel control valve known as"S-valve" or"spitting valve". Parameters of the model were: particle diameter and density (rice, green coffee beans and lentil), relative diameter of the horizontal section of the valve, system operation pressure and air superficial velocity. Two S-valves prototypes, built in acrylic pipe of 0.04 and 0.02 meters diameter, were used. The experiments were run at room temperature and at two operation pressures of 7 and 8 105 Pa. For the grains we used, the obtained model fit experimental data reasonable well (98% for rice, 85% for green coffee beans, and 97% for lentil).