| dc.description.abstract | The small scale and length of time, in addition to the exciting phenomena (such as the
inner processes within the fluid) presented by droplets and thin films, make experimen
tal observations difficult and, thus require the need for computational models capable
of reproducing these processes in engineering. Current computational models are
dominated by Finite Element and Finite Volume methods; whilst this has advanced
to a high level of improvement and understanding, they however, lack the capacity
to capture large deformations adequately and applied on complex systems, which is
mainly due to its dependence on their mesh requirements. The present research pro
posed and developed a new method of solving thin films and droplet problems using
a full Lagrangian approach known as Smoothed Particle Hydrodynamics (SPH). SPH
solves the continuum set of conservation equations and provides the ability to accu
rately track the fluid or material history throughout its lifetime. The thesis explores
and develops new and novel single phase SPH models to reliably treat and handle the
dynamic nature of surface tension effects over long simulation time scales. In particu
lar, Intermolecular Interaction Force (IIF), Continuum Surface Force (CSF), Contact
Line Force (CLF) and Disjoining Pressure (DP) models are developed and applied
on a variety of surface tension dominated flow problems and the results, where possi
ble, are validated against known analytical and experimental findings, which include
investigations of droplet oscillation, wetting on substrate, contact angle hysteresis
and thin film rivulet flows to highlight the capability of the proposed developed SPH
methodology and models. The SPH solver is developed from scratch using C++ to
maximise extensibility of the methodology and computational performance. | en_US |
