Experimental study on resonantly forced interfacial waves in a stratified circular cylindrical basin

• Published in: Journal of fluid mechanics Vol. 582; pp. 203 - 222
• Main Authors: WAKE, GEOFFREY W., HOPFINGER, EMIL J., IVEY, GREGORY N.
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 10.07.2007; Cambridge University Press (CUP)
• Subjects: Engineering Sciences; Environmental engineering; Exact sciences and technology; Experiments; Fluid dynamics; Fluid mechanics; Fluids mechanics; Fundamental areas of phenomenology (including applications); Hydrodynamic waves; Hydrology; Mechanics; Physics; Shallow water; Water depth; Test facilities; Liquid liquid interface; Free surface flow; Two layer medium; Resonance; Experimental study; Shallow water; Oscillating vessel; Liquid sloshing
• ISSN: 0022-1120; 1469-7645
• DOI: 10.1017/S002211200700585X

Laboratory experiments have been performed on resonantly forced interfacial waves in a circular cylindrical basin containing a two-layer stratified fluid. The results of this shallow-water study exhibit a number of similarities to previous shallow-water studies performed in single-layer fluids, such as the generation of a large-amplitude response over a frequency bandwidth offset from the primary resonance, generation of a swirling mode at the observed resonant condition, and the significant contribution of higher harmonics. The two-layer experiments also produce results that are unique to stratified domains. In particular, the observed negative nonlinearity of the resonant condition at shallow water depth, mixing of the density interface resulting in detuning the forced response from the resonant condition, the enhanced role of viscous dissipation, and an alternative pathway for the nonlinear generation of higher-frequency waves when the layer depths are disparate. The results of this study are considered with regard to their implications for enclosed basins at the geophysical scale that are subject to near resonant forcing.