A density oscillator model
A. Hubardª, C. Málagab, H. Arceb, and H. Gonzálezb
ª Benjamin Levich Institute, City College of CUNY, 140th Street and Convent Avenue, New York, N.Y. 10031, USA.
b Departamento de Física, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City 04510, D.F. Mexico.
]]> Recibido el 12 de junio de 2012;
Abstract
We present a model equation describing the behavior of a density oscillator and a set of experiments to test the model. The system consists of a cup containing salty water with an orifice in its base, partially submerged in an outer vessel filled with fresh water. Such a setup produces an oscillatory flow of water through the orifice. The density oscillator is an oscillatory system that shares common features with more complex systems with a stable limit cycle. Although a Rayleigh equation has been used as a model equation for these systems, we propose a different approach based on the integration of the hydrodynamic equations on a streamline. The model reproduces the experimental oscillation and predicts the period as a function of the physical parameters. Phase resetting curves observed in experiments under external biphasic excitation can be reproduced by the model.
Keywords: Density oscillator; saline oscillator; non linear oscillators.
PACS: 47.20.Bp; 82.40.Bj
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]]>Acknowledgements
We want to thank Michel Guevara for his revision and valuable comments. Jaime Garcia for his support with the experimental setup; Alicia Falcon and Araceli Torres for their help with data acquisition. This work was partially funded by PAPIIT-UNAM IN118611.
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