Sloshing in Suspended Containers

Cooker ({\it Wave Motion}, {\bf 20}, 1994) reported original work on the interactive dynamics between a fluid partially filling a single-compartment container suspended as a bifilar pendulum to determine the frequency of small amplitude motion of the system. Weidman ({\it Bull. APS}, {\bf 39}, 1994) extended the results of Cooker to include, {\it inter alia}, multi-compartment rectangular containers and a cylindrical container. Fundamental mode frequency measurements of the suspended system are presented here for fluids partially filling single- and multiple-compartment rectangular containers and a cylindrical container. The results confirm the validity of the shallow-water approach over a range of fluid/container mass ratios $M$ and pendulum lengths $l$ varying from 0.5~m to 3.5~m. The frequency approach to unconstrained container motion in the limit $l \to \infty$ is also evident.