Experimental design of a system to investigate chaotic dripping

We report here the construction of a system designed to investigate chaotic dripping behaviour. The benchtop system has been designed for the purpose of measuring chaotic dripping in a microgravity test facility, although measurements under normal gravity only are reported here. The results confirm the main predictions of a simple 1-D mass-spring-damper theoretical model of the system, including the formation of point attractors and associated limit cycles, although there are significant departures from this model within specific flow rate regions resulting in the formation of what are termed here 'mid' drops (drops of a smaller size than normal). It is hypothesized that the origin of these mid drops arises from the development of a 'wetting' mass, namely a mass of liquid that is evacuated from the delivery tube from the previous drop excision.