Edge Fillet Radius Effect on Acoustic Energy in an Ultrasonic Microcontainer for Preparing Nanoemulsion

Nanoemulsion preparation and improvement play a pivotal role in the area of pharmaceuticals, food, mechanical, and chemical engineering. The ultrasonic technique is one of the most commonly used methods in preparing nanoemulsion, related to mechanical and electrical engineering. The present study aimed to evaluate the effect of edge fillet radius in four different layouts of a cubic ultrasonic microcontainer at different frequencies through 36 simulations by using COMSOL Multiphysics software. To this aim, the simulations were performed in three edge fillet radius values of zero, 2.5 and 5 mm, and at the excitation frequencies of 20, 200 and 300 kHz. In this regard, experimental tests were carried out in two modes of: a) regular ultrasonic bath (RUB) and b) filleted-edges ultrasonic bath (FEUB). Based on the simulation and experimental results, the removal of sharp edges has a positive influence on propagating waves, leading to an increase in the acoustic energy density at different frequencies and the effect was more significant at lower frequencies and layouts with more PZTs.