This project aims to control the droplet size distribution produced by rotary atomizers by adjusting the shape and wettability of the rotating surface

Rotary atomizers are simple devices which allow the break-up of a fluid stream into small droplets. They involve a fluid jet impinging vertically at the centre of a rotating surface. Under the effect of the centrifugal force, the fluid spreads outwards and forms a film which evolves into ligaments at the rim which ultimately break up into droplets.

Rotary atomizers are routinely used in a range of industrial applications including spray dryers to produce powders in the food industry, painting, microencapsulation, the production of pharmaceuticals, or agricultural sprays for which it is important to maximise the amount of exposed fluid surface area per unit volume.

It is well-known that the shape and nature of the spinning surface in the atomizer is a determining factor in the droplet size distribution but the complexity of the underpinning multiphase, multiscale flow on a curved, rotating surface has impaired progress in rotary atomizer design informed by systematic and rigorous mathematical modelling and numerical simulations.

This project aims to shed light on the relationship between the shape and wettability of the rotating surface and the resulting droplet size distribution of rotary atomizers using flow stability analysis and direct numerical simulations.

The candidate will be based at the University of Canterbury in Christchurch, New Zealand and part of an international collaboration with EPFL in Lausanne, Switzerland.