Modeling and Comparison with Experiment of SAW Induced Water Droplet Motion

Abstract

A water droplet motion on a piezoelectric substrate, which is actuated using Surface Acoustic Waves (SAW), is presented toward water desalination purposes. The processes of fluid flow motion under different RF powers and SAW frequencies, induced by internal streaming, has been observed both experimentally and numerically. A free droplet dynamics in the volume of 2 and 5 μl interacted with intensive SAW on the piezoelectric substrate surface for 34 and 58 MHz frequencies, and power output between 0-4 dBm observed. In tha paper a three-dimensional (3D) finite element model using computational fluid dynamics approach of the free water droplet motion was developed. The different dependences of microfluidic performance such as locally streaming lines, slip length and droplet motion velocity have been studied.