Controlling Chaos in a Thermal Convection Loop
نویسندگان
چکیده
It is demonstrated experimentally and theoretically that through the use of an active (feedback) controller one can dramatically modify the nature of the flow in a toroidal thermal convection loop heated from below and cooled from above. In particular, we show how a simple control strategy can be used to suppress (laminarize) the naturally occurring chaotic motion or induce chaos in otherwise time-independent flow. The control strategy consists of sensing the deviation of fluid temperatures from desired values at a number of locations inside the loop and then altering the wall heating to either counteract or enhance such deviations. Disciplines Engineering | Mechanical Engineering Comments Suggested Citation: Wang, Yuzhou, Jonathan Singer and Haim H. Bau. (1992). Controling chaos in a thermal convection loop. Journal of Fluid Mechanics. Vol. 237. p.479-498. Copyright 1992 Cambridge University Press. http://dx.doi.org/10.1017/S0022112092003501 This journal article is available at ScholarlyCommons: http://repository.upenn.edu/meam_papers/199 J . Fluid Meeh. (1992), tml . 237, p p . 479-498 Printed in Great Britain 479 Controlling chaos in a thermal convection loop By Y U Z H O U WANG, JONATHAN SINGER AND HAIM H. B A U t Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, PA 19104-6315, USA (Received 24 May 1991) It is demonstrated experimentally and theoretically that through the use of an active (feedback) controller one can dramatically modify the nature of the flow in a toroidal thermal convection loop heated from below and cooled from above. In particular, we show how a simple control strategy can be used to suppress (laminarize) the naturally occurring chaotic motion or induce chaos in otherwise time-independent flow. The control strategy consists of sensing the deviation of fluid temperatures from desired values at a number of locations inside the loop and then altering the wall heating to either counteract or enhance such deviations.
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