Preliminary results of the sounding rocket experiment on oscillatory Marangoni flows in liquid bridge

This paper reports on the results of the experiment PULSAR (Pulsating and Rotating Instabilities in Oscillatory Marangoni Flows), performed on the MAXUS 4 sounding rocket launched in April 2001 from the Swedish base in Kiruna. Aim of the experiment was the analysis of the three-dimensional and time-dependent flow regimes arising in a liquid bridge of Silicone oil when the temperature difference between the disks is increased. Pulsating and rotating oscillatory regimes have been established during the microgravity time at different temperature differences across the liquid bridge. The oscillatoy flow has been detected by visual observation of the flow field organization (using a CCD camera and silver-coated tracers), by the behaviour of the temperatures, measured by thin thermocouples at different azimuthal coordinates, and by the evolution of the surface temperature distribution, measured by an infrared camera.