Investigación

 

A density oscillator model

 

A. Hubardª, C. Málaga^b, H. Arce^b, and H. González^b

 

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;
Aceptado el 9 de agosto 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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