The use of scale model to study film flow in a rotary atomizer cup

Abstract

The aim of this chapter is to simulate processes of liquid droplet formation and atomization in a typical automotive paint spray system with scale modeling technique. In a spray painting process, paint is sprayed by a bell sprayer cup rotating at high speed to create fine atomized paint particles. The bell sprayers typically rotate at a speed of 30,000 rpm and have liquid (paint) flowing from the center with a flow rate of 300 cc/min. Due to the centrifugal action of the rotation, the liquid flows to the exterior of the bell, where they pass through grooves leading to the formation of ligaments and henceforth droplets due to shear forces acting against the surface tension forces. We designed different types of scale models to simulate the process.