Integrated Characterization of Hydrodynamic Cavitation: Optical, Chemical, and Simulation Correlations

Abstract

Hydrodynamic cavitation (HC) is an advanced oxidation process for degrading micropollutants, primarily driven by hydroxyl radicals ($OH\cdot$$OH\cdot$). This study addresses the research gap by characterizing HC under high upstream pressures (up to 60 bar) and integrating chemical, optical, and simulation approaches for a comprehensive characterization of HC processes. OH radical production was quantified with salicylic acid, and bisphenol A (BPA) degradation experiments validated their role in oxidation reactions. Optical methods captured cavitation jet and luminol chemiluminescent images, while simulations estimated vapor bubble formation and cavitation gas fractions. This research focuses on the high-pressure range of 10 to 60 bar in HC systems, demonstrating a proportional relationship between pressure and both the production rate of OH radical and the rate constants of BPA degradation. At 60 bar, the highest concentration of OH radicals and BPA degradation rate were observed. This research enhances the understanding of HC and its potential for optimized pollution control.