Characterisation of a wavy convective instability in Poiseuille-Rayleigh- Bénard flows: Linear stability analysis and non linear numerical simulations under random excitations

Xavier Nicolas (1) , S. Xin (2) , N. Zoueidi (1)

1 TCM
2 CETHIL - Centre de Thermique de Lyon

The aim of the present paper is to characterize a secondary convective instability of Poiseuille-Rayleigh-Bénard (PRB) mixed convection flows in air that takes the shape of wavy thermoconvective rolls, for 70≤Re≤300 and 30003Ra *. Comparisons with the experiments by Pabiou et al. [JFM, 2005] are proposed.

Mots clés: Convectie instabilities; longitudinal rolls; wavy rolls; Channel inlets; Convective instabilities; Infinite plate; Mixed convection flow; Random excitations; Space and time evolution; Aspect ratio; Heat transfer; Computer simulation; linear stability; direct simulation

Domaines: Mécanique des fluides [physics.class-ph]; Mécanique des fluides [physics.class-ph]

Xavier Nicolas, S. Xin, N. Zoueidi. Characterisation of a wavy convective instability in Poiseuille-Rayleigh- Bénard flows: Linear stability analysis and non linear numerical simulations under random excitations. 2010 14th International Heat Transfer Conference, IHTC14, Aug 2010, Washington, DC, United States. pp.203-208. ⟨hal-00711387⟩