Study on the Fluidic Component of the Complete Fluidic Sprinkler

Abstract

The PXH fluidic sprinkler controlled by the outlet clearance is a new type sprinkler which is driven and controlled by the Coanda effect. This paper analyzes the offset jet with control stream in the simplified model. Based on the special design of the fluidic component of the fluidic sprinkler, a control stream coefficient was proposed and the air entrance hole distance was considered as one of the key factors that, influence the offset flow field. Based on the numerical simulations and the experiments, the influences made by different air entrance hole distances, offset ratios, and working pressures on the water-air two-phase flow field of the simplified fluidic component have been studied. The offset distance, the pressure distribution on the offset wall, the yaw angle of the main jet flow and their variations with the pressure, and the structural parameters were obtained. The air velocity variation in the air entrance hole was regarded as the judgment for a complete attachment. Visualization experiments and pressure distribution experiments were carried out and the experimental results show a good agreement with simulation results.