Soret and Dufour effects on thresholds of stability in a horizontal Brinkman porous layer submitted to vertical temperature and species gradients using linear and non-linear analysis. (August 2022)

• Record Type: Journal Article
• Authors: Filahi, Ismail; Amahmid, Abdelkhalek; Bourich, Mohamed; Hasnaoui, Mohammed
• Is Part Of: Proceedings of the Institution of Mechanical Engineers. Volume 236:Number 15(2022)
• Page Start: 8767
• Page End: 8783
• Publication Date: 2022-08
• Subjects: Soret and Dufour effects -- double diffusion -- linear and non-linear stability analysis -- brinkmann porous layer -- Hopf bifurcation -- subcritical bifurcation -- supercritical bifurcation; Mechanical engineering -- Periodicals; 621.05
• DOI: 10.1177/09544062221086231
• Languages: English
• ISSNs: 0954-4062

Abstract

The present study deals with Soret and Dufour effects on the onset of double-diffusive natural convection in a horizontal Brinkman porous layer with a free-stress upper boundary. The thresholds of stationary, oscillatory, and subcritical bifurcations are derived on the basis of linear and non-linear analysis, as functions of the governing parameters. The effect of Dufour (D u ) and Soret( S r ) parameters on the thresholds of instabilities is illustrated and discussed. There are critical combinations( S r, D u ) for which the thresholds of supercritical bifurcations are independent of the buoyancy ratio. Particularly, forD u = 0 andS r = L e / ( 1 + L e ), the stationary convection starts at the threshold of the pure thermal convection whatever the value of the buoyancy ratio.