MSc Thesis Defense: Mohammad Imanzadeh, DISSOLVED GAS ROLE IN THE HYDRODYNAMIC CAVITATION-ON-A-CHIP CONCEPT (HC), Date & Time: 14 July, 2026 – 3:00 PM, Place: L027

DISSOLVED GAS ROLE IN THE HYDRODYNAMIC CAVITATION-ON-A-CHIP CONCEPT (HC)

Mohammad Imanzadeh
Mechatronics Engineering, MSc Thesis , 2026

Thesis Jury

     Asst. Prof. Morteza Ghorbani (Thesis Advisor)

  Prof. Ali Koşar (Thesis Co-Advisor)

Prof. Emre Erdem

Asst. Prof. Melih Türkseven

  Prof. Iakovos Tzanakis

Date & Time: 14th July, 2026 –  3:00 PM

Place: FENS L027

Keywords : Hydrodynamic Cavitation, Microfluidics, Dissolved Gases, Carbon Dioxide (CO₂), Oxygen (O₂)

Abstract

Hydrodynamic cavitation (HC) has emerged as a promising technique for enhancing gas–liquid mass transfer, process intensification, advanced oxidation, and microfluidic applications. Although cavitation behavior is known to depend on hydraulic conditions and reactor geometry, the influence of dissolved gases on microscale hydrodynamic cavitation remains insufficiently understood. This thesis experimentally investigates the role of dissolved gases in hydrodynamic cavitation-on-a-chip through two complementary studies involving dissolved carbon dioxide (CO₂) and dissolved oxygen (O₂).Hydrodynamic cavitation was generated in transparent microfluidic reactors under controlled operating conditions, enabling direct high-speed visualization of transient vapor structures. Quantitative image analysis, including void fraction mapping, Proper Orthogonal Decomposition (POD), and Power Spectral Density (PSD), was employed to characterize cavitation dynamics. Additional physicochemical analyses, including dissolved gas measurements and potassium iodide (KI) dosimetry, were performed to evaluate gas transfer and cavitation-induced oxidative activity.The results demonstrate that dissolved CO₂ lowers the cavitation inception pressure, modifies cavity morphology, suppresses high-frequency bubble-collapse oscillations, and enhances cavitation-assisted CO₂ removal. In contrast, dissolved O₂ primarily influences cavity organization, coherent flow structures, modal energy distribution, oxygen transfer, and oxidative activity. Reactor geometry was found to strongly affect these gas-dependent phenomena by altering pressure gradients, residence time, and bubble evolution.Overall, the findings establish dissolved gas composition as an effective control parameter for hydrodynamic cavitation in confined microfluidic systems. The integrated experimental methodology developed in this work provides new insight into dissolved-gas-controlled cavitation and offers practical guidance for the design and optimization of cavitation-on-a-chip technologies for environmental, chemical, and process engineering applications.