Defense Date
2024
Document Type
Thesis
Degree Name
Master of Science
Department
Mechanical and Nuclear Engineering
First Advisor
Reza Mohammadi
Abstract
A PRECISION-CONTROLLED INVESTIGATION INTO THE FUNDAMENTALS WHICH DRIVE THE INCREDIBLE SUPERHYDROPHOBIC PROPERTIES OF SOOT
By Ashton Bressler
A thesis submitted as a partial fulfilment of the Virginia Commonwealth University requirements for a Masters of Science at Virginia Commonwealth University.
Virginia Commonwealth University, 2024.
This thesis investigates a precision controlled superhydrophobic soot surface, composed of semi-rigid linked chains of spheres, with a radii of roughly 14um. These spheres have exceptionally useful hydrophobic properties due to; their large surface area, their large triple phase line length, their low area fraction of solid-liquid interface, their ability to deform, and their strength from both the DLC bond formed in combustion and the ability of the cross linked lattice to support itself under pressure.
A custom system was built to precisely control the flow rate of rapeseed oil through a cutting torch and into a combustion chamber being fed varied amounts of oxygen to support the combustion process. The Methodology section covers the iterations which led to the design of the combustion process. Samples were then analyzed under a SEM and their advancing and receding contact angle measurements were recorded.
This thesis provides an in-depth understanding of surface energy balance and its role in wetting. The major topical areas covered in this thesis as listed below:
* The significance of roughness
* The advantages of the Cassie-Baxter state to anti wetting
* Complications around creating a surface which can stay in this Cassie-Baxter state
* Problems with the fragility of superhydrophobic surfaces
* Hydrophobic properties, as they relate to triple-phase line energies.
Rights
© The Author
Is Part Of
VCU University Archives
Is Part Of
VCU Theses and Dissertations
Date of Submission
4-30-2024
Comments
This thesis is a good educational tool for learning about wetting.