Use this URL to cite or link to this record in EThOS:
Title: Fluid dynamics in nanoscale systems with amorphous surfaces and the interaction of nanoparticles with surfactant layers
Author: Groombridge, Matthew
ISNI:       0000 0004 2737 1864
Awarding Body: Imperial College London
Current Institution: Imperial College London
Date of Award: 2013
Availability of Full Text:
Access from EThOS:
Access from Institution:
The flow properties of fluids confined within nanoscale pores have been investigated. This study attempts to increase the understanding of some of the factors which affect flow over amorphous surfaces. Direct comparisons are made between experimental data and theoretical systems. Equilibrium and non-equilibrium methods are used to calculate the slip coefficient and a relaxation time, which is related to the interfacial friction. This is shown to be a simple and reliable way of predicting flow behaviour across a wide range of systems with different structures. Other methods, such as those based on Maxwell’s model, are found to be less reliable in systems with very rough surfaces. Enhanced flow rates, as found in some experimental systems, would have enormous benefits in a nanofluidic device. The flow dynamics in a variety of systems with different surface roughnesses and chemical compositions have been determined. The flow of water and decane fluids over a variety of carbon surfaces have been studied. Flow over PDMS surfaces with varying levels of oxidation has also been analysed. Enhancements are found to be lower than those predicted experimentally. There is a wide interest in the effects of inhalation of nanoparticles on lung tissues. In this work, the interactions of several environmentally interesting nanoparticles (fullerenes and titanium dioxide) with a model lung membrane have been simulated. The trajectories and interactions of the nanoparticles with the membranes are studied. Hydrophobic particles are found to sit amongst the lipid tails, hydrophillic particles nearer the water/lipid interface. Although no particles are found to cross freely into the water layer, an interesting effect is noted whereby water molecules are seen to leave the water phase of the membrane and coat the surface of hydrophilic nanoparticles. For the largest nanoparticles this creates a bridge across the membrane from the water phase to the vacuum.
Supervisor: Quirke, Nick ; Bresme, Fernando Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral