Representation of Typical Droplet Shapes in 2D Latent Space

In this study, we investigate the clustering of 5000 droplets, each originating from one of five distinct droplet classes, each representing a unique geometry. The shape coordinates of the droplets are mapped to a 2D latent space through a two-step, fully reversible process involving Fourier series and autoencoders. Thus, each droplet contour sampled by 400 points is represented by 2 scalar numbers. We present data mapping 5000 droplets in two-dimensional space, which reveals ringlike clusters. Each cluster corresponds to a distinct droplet class, with the classification based on the droplet morphology, which is known a priori. Further, we find that well-known clustering algorithms like DBSCAN show limited success in identifying these ring-shaped clusters underscoring the need to explore alternative clustering approaches, particularly those tailored to handle ring-shaped distributed data.