In this thesis, the phenomenon of a microdrop impacting onto and spreading over surfaces of constant and variable wettability is investigated. The study is motivated by wide-ranging industrial applications of ink-jet printing technologies, in particular used by our industrial sponsor Kodak Ltd. Mathematical models for dynamic wetting phenomena are incorporated into a specially developed finite element based numerical platform. By examining different models, it was found for the first time that the interface formation model is capable of describing the experimentally observed non-uniqueness of the relationship between the contact-line speed and the dynamic contact angle. It is shown that, the interface formation model naturally captures the effect which variations in the wettability of the solid surface have on an adjacent flow, so that the model can be used, without any ad-hoc alterations, to consider the spreading of microdrops on such solids. An investigation of the effect that variation of the model's parameters has on the characteristics of the impact and spreading of microdrops has been carried out.
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