Open AccessThe onset of Marangoni bio-thermal convection in a layer of fluid containing gyrotactic microorganisms
Author(s) -
Latifa Khayyat,
Abdullah A. Abdullah
Publication year - 2021
Publication title -
aims mathematics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.329
H-Index - 15
ISSN - 2473-6988
DOI - 10.3934/math.2021787
Subject(s) - marangoni number , marangoni effect , convection , mechanics , lewis number , thermal , boundary layer , physics , thermophoresis , eigenvalues and eigenvectors , chemistry , materials science , thermodynamics , heat transfer , mass transfer , nanofluid , quantum mechanics
The problem of the onset of Marangoni bio-thermal convection is investigated for a horizontal layer of fluid containing motile gyrotactic microorganisms. The fluid layer is assumed to rest on a rigid surface with fixed temperature and the top boundary of the layer is assumed to be a free non deformable surface. The resulting equations of the problem constitute an eigenvalue problem which is solved using the Chebyshev tau numerical method. The critical values of the thermal Marangoni number are calculated for several values of the bioconvection Péclet number, bioconvection Marangoni number, bioconvection Lewis number and gyrotaxis number. The results of this study showed that the existence of gyrotactic microorganisms increases the critical thermal Marangoni numbers. Moreover, the critical eigenvalues obtained were real-valued indicating that the mode of instability is via a stationary mode, however oscillatory mode is possible for some ranges of the parameters values.