In this work, we will describe experiments designed to focus on droplet wall interactions. Specifically, the experiments involved single droplets and droplet pairs impinging on a target. The target was heated to a known temperature, and heat transfer from the target by the drops was measured. The hydrodynamics of the droplet-wall interaction were recorded by a high speed camera to capture the details of each droplet-surface interaction.
For multiple droplet impingements, in addition to the single droplet parameters of Weber number, Reynolds number, and surface temperature, we included a parameter related to droplet spacing prior to impact, and the number of droplets which can interact.
This paper will emphasize the heat transfer results from this experiment for single particles and particle pairs. The fluid used in the results shown was water. Several wall temperatures were used (100 C, 200 C, and 400 C), corresponding to near-saturation temperature conditions and much higher than saturation conditions. The results show the heat transfer rate as a function of target surface temperature and the droplet spacing for the droplet pairs.