Numerical and experimental modeling of the stability of the flow of thermoviscous fluid in an annular channel
Authors
Kireev V.N.
Ufa University of Science and Technology
Mukhutdinovа A.A.
Mavlyutov Institute of Mechanics Ufa Federal Research Centre of the Russian Academy of Sciences
Nizampva A.D.
Mavlyutov Institute of Mechanics, Ufa Federal Research Centre of the Russian Academy of Sciences
Urmancheev S.F.
Mavlyutov Institute of Mechanics, Ufa Federal Research Center of RAS
Keywords:
hydrodynamic stability, thermoviscosity parameter, weakly nonlinear stability theory, annular channel, temperature gradient, Reynolds number
Abstract
This paper presents the results of a study of fluid flow stability taking into account the viscosity dependence on temperature. A 45% aqueous solution of propylene glycol was used as the working fluid. The mathematical model was constructed in accordance with the basic principles of the weakly nonlinear theory of hydrodynamic stability. The experiments were conducted on a setup based on two horizontally located coaxial pipes made of transparent material. The inner pipe contained a heating element to create a temperature gradient in the cross-section of the annular channel. The transition from laminar to turbulent flow was determined visually using tinted liquid.The calculations showed that the temperature gradient in the channel cross-section leads to a decrease in the critical Reynolds number, and the minimum critical Reynolds number decreases with an increase in the liquid thermal viscosity parameter. The calcula- tion results were convincingly confirmed by experimental data.
