Coupled Gas-Liquid-Structure Systems: Part 2—Applications

In the companion paper, Joos and Huber (1987) have developed an analysis that applies to certain types of systems in which a hydrodynamic transient creates pressure forces dependent on the flexibilities of the liquid boundary surfaces. To test the analysis we performed two pairs of experiments. Each pair involved identical experiments conducted in two geometrically identical cylindrical tanks. One tank was rigid, the other flexible. In the first set of experiments a gas bubble oscillated freely in a container partially filled with liquid. We compared experimentally measured natural frequencies with those predicted theoretically. In the second set of experiments a complex hydrodynamic transient was produced by injecting air into a tank partially filled with liquid. Using data from the rigid system experiments we predict the pressures and wall displacements in the flexible system and compare these predictions with measurements made in the flexible test tank. The inverse problem—predicting the pressures in the rigid tank from data obtained in the flexible tank—is also analyzed using the theoretical tools we have developed, and again predictions are compared with experiment.