Thesis Defense – Mustafa Aykan Uzun (MSME)

Mustafa Aykan Uzun – M.Sc. in Mechanical Engineering

Assoc. Prof. Özgür Ertunç – Advisor

Date: 27/12/2024

Time: 11:00

Location: AB1 409

“Analysis Of Flow in Open-End Pressure Swirl Atomizers”

Assoc. Prof. Özgür Ertunç, Özyeğin University

Prof. Oğuz Uzol, Middle East Technical University 

Asst. Prof. Altuğ Melik Başol, Özyeğin University

Abstract:

In this study, high-fidelity 3D and 2D axisymmetric CFD simulations of open-end pressure swirl atomizers (PSA) were conducted using the VOF method and a second-order accurate solution of the incompressible Navier-Stokes equations (Quasi-DNS). The aim was to investigate the internal flow characteristics of PSAs while eliminating inlet and contraction effects by using ideal continuous ring-like inlet and open-end PSA. Simulations revealed the formation of Görtler vortices in the swirling liquid film, attributed to flow separation near the inlet. Further 3D axial inlet simulation demonstrated that Görtler vortices can form independently of inlet separation. A modified Görtler number suitable for two-phase swirling films was developed, and the impact of these vortices on liquid film and spray characteristics was examined. While the vortices resulted in linear velocity profiles in the liquid film, they did not significantly affect key PSA performance parameters, such as pressure drop, film thickness, or spray angle. Based on these findings, a blade-type inlet was designed.

Bio:

Mustafa Aykan Uzun graduated from the Mechanical Department at Özyeğin University (OzU) in February 2022, where he is currently a researcher in the Fluid Mechanics Spray Laboratory. His research focuses spray mechanism and design of pressure swirl atomizers.