The Shapes of Valves and Emulsification Action in a Homogenizer

Abstract

The homogenizer basically consists of a high-pressure plunger pump usually with triple plungers to minimize pressure fluctuations and a homogenizing valve with a narrow gap. However, the flow within the homogenizing valve is not clarified theoretically. In this paper, the influence of shape modification of the homogenizing valve was investigated in the emulsification action. The experiments using a small homogenizer are conducted. We studied the influence of the flow pattern (pressure distributions, shear stress) on the droplet size distribution obtained in the experiment, and investigated the relation between the shear flow and the emulsification action in the homogenizing valve. In this experiment, two valve types (sharp type and flat type) were applied. The pressure drop in the valve and the parallel gap part length were changed. The droplet size distribution results obtained in the emulsification tests could be analyzed based on the average value of the wall shear stress in the parallel gap part through the above experiments and calculation results.