Topical Problems of Fluid Mechanics


Institute of Thermomechanics AS CR, v.v.i.	CTU in Prague Faculty of Mech. Engineering Dept. Tech. Mathematics	MIO Université du Sud Toulon Var - AMU - CNRS - IRD	Czech Pilot centre ERCOFTAC

Discussion of Extremal Principles for Turbulent Flow Based on Hypothesis of Maximum Entropy Production
Hyhlík T.
Abstract:
The formulation of fundamental thermodynamics inequality representing second law of thermodynamics is given. The entropy production is expressed in the flow of Newtonian fluid. An overall entropy production is evaluated for case of selected basic flow configurations like pipe flow and boundary layer. Both the principle of maximal rate of kinetic energy dissipation and the principle of maximal kinetic energy production are formulated and discussed. By using variational calculus it is shown that flow configurations in equilibrium of turbulent kinetic energy production and dissipation such as channel flow, pipe flow and boundary layer are consistent with principle of maximal entropy production. It is shown that laminar flow is consistent with principle of minimal entropy production.
Keywords:
entropy production, extremal principles, turbulent flow

Fulltext: PDF DOI: http://dx.doi.org/10.14311/TPFM.2016.010

In Proceedings Topical Problems of Fluid Mechanics 2016, Prague, 2016 Edited by David Šimurda and Tomáš Bodnár, pp. 69-74 ISBN 978-80-87012-58-1 (Print) ISSN 2336-5781 (Print)