Thesis Defense -Anıl Yılmaz (MSME)

Anıl Yılmaz - M.Sc.Mechanical Engineering

Asst.Prof. Özgür ERTUNÇ  – Advisor

Date: 13.01.2021

Time: 11:00

Location: This meeting will be held ONLINE. 

https://ozyegin-edu-tr.zoom.us/j/91305210430?pwd=K0tDZ2p3eXl6RWNaRGorTG85YlBrQT09

Meeting ID: 913 0521 0430
Passcode: 477226

3-D SIMULATION OF DROPLET IMPACT ON STATIC

AND MOVING WALLS

Thesis Committee:

Asst.Prof. Özgür Ertunç , Özyeğin University

Asst.Prof. Altuğ Melik Başol, Özyeğin University

Asst.Prof. Ayşe Gül Güngör, İstanbul Technical University

Abstract:

In the present study, the contact angle model and origin of the parasitic current have been studied to provide an accurate prediction of droplet surface interactions in the Volume of Fluid (VOF) framework. We investigate the effect of “modeled" dynamic contact angle boundary conditions on 3D droplet force balance and the parasitic currents relation with grid distribution. According to the simulation experience, OpenFOAM's static and classical dynamic contact angle calculations are insufficient to provide accurate droplet spread and deposition ratio. In fact, it was shown that the classical

Kistler dynamic contact angle model did not perform well in low capillary numbers

and in cases where the difference in advancing and receding angles was high. It has been possible to reduce the unphysical ow problem seen in the interface region in multiphase simulations with structural changes. It has been modeled that the number of central volume neighbor face and cell shape affects the gradient calculations associated with the formation of parasitic current. It has been observed that the polyhedral cell structure is more stable than the cartesian structure for the interface gradient calculations. To examine the dynamics in different physical conditions, we compared simulations with basic experiments to understand whether those models work. We then simulated possible droplet outcome cases (deposition, partial rebound, and split deposition) on stationary and moving smooth surface conditions, and simulation results were consistent with experimental results.

Bio: 

Anıl Yılmaz received the B.Sc. degree in Mechanical Engineering from Kocaeli University, Kocaeli, Turkey in 2016 and he is currently pursuing the M.Sc. degree in Mechanical Engineering at Ozyegin University. His research areas are multiphase flow simulations and mathematical modeling.