Non-Boussinesq stability analysis of natural-convection gaseous flow on inclined hot plates

Rajamanickam, P.; Coenen, Wilfried; Sánchez, Antonio L.

Publication:
Non-Boussinesq stability analysis of natural-convection gaseous flow on inclined hot plates

dc.affiliation.dpto	UC3M. Departamento de Ingeniería Térmica y de Fluidos	es
dc.affiliation.grupoinv	UC3M. Grupo de Investigación: Ingeniería de Sistemas Energéticos	es
dc.contributor.author	Rajamanickam, P.
dc.contributor.author	Coenen, Wilfried
dc.contributor.author	Sánchez, Antonio L.
dc.date.accessioned	2022-09-01T08:08:23Z
dc.date.available	2022-09-01T08:08:23Z
dc.date.issued	2017-06
dc.description.abstract	The buoyancy-driven boundary-layer flow that develops over a semi-infinite inclined hot plate is known to become unstable at a finite distance from the leading edge, characterized by a critical value of the Grashof number Gr based on the local boundary-layer thickness. The nature of the resulting instability depends on the inclination angle /, measured from the vertical direction. For values of / below a critical value /c the instability is characterized by the appearance of spanwise traveling waves, whereas for/ > /c the bifurcated flow displays Görtler-like streamwise vortices. The Boussinesq approximation, employed in previous linear stability analyses, ceases to be valid for gaseous flow when the wall-to- ambient temperature ratio Hw is not close to unity. The corresponding non-Boussinesq analysis is pre- sented here, accounting also for the variation with temperature of the different transport properties. A temporal stability analysis including nonparallel effects of the base flow is used to determine curves of neutral stability, which are then employed to delineate the dependences of the critical Grashof number and of its associated wave length on the inclination angle / and on the temperature ratio Hw for the two instability modes, giving quantitative information of interest for configurations with Hw 1 1. The analysis provides in particular the predicted dependence of the crossover inclination angle /c on Hw , indicating that for gaseous flow with Hw 1 1 spanwise traveling waves are predominant over a range of inclination angles 0 6 / 6 /c that is significantly wider than that predicted in the Boussinesq approximation.	en
dc.format.extent	8
dc.identifier.bibliographicCitation	Rajamanickam, P., Coenen, W., & Sánchez, A. L. (2017). Non-Boussinesq stability analysis of natural-convection gaseous flow on inclined hot plates. In International Journal of Heat and Mass Transfer, 109, 949–957	en
dc.identifier.doi	http://dx.doi.org/10.1016/j.ijheatmasstransfer.2017.02.010
dc.identifier.issn	0017-9310
dc.identifier.publicationfirstpage	949
dc.identifier.publicationlastpage	957
dc.identifier.publicationtitle	INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER	en
dc.identifier.publicationvolume	109
dc.identifier.uri	https://hdl.handle.net/10016/35617
dc.identifier.uxxi	AR/0000029364
dc.language.iso	eng	en
dc.publisher	Elsevier BV	en
dc.relation.publisherversion	https://www.sciencedirect.com/science/article/pii/S0017931016334482?via%3Dihub	en
dc.rights	© 2017 Elsevier Ltd. All rights reserved.	en
dc.rights	Atribución-NoComercial-SinDerivadas 3.0 España	*
dc.rights.accessRights	open access	en
dc.rights.uri	http://creativecommons.org/licenses/by-nc-nd/3.0/es/	*
dc.subject.eciencia	Ingeniería Mecánica	es
dc.subject.other	Natural convection	en
dc.subject.other	Inclined hot plate	en
dc.subject.other	Non-boussinesq effects	en
dc.subject.other	Vortex instability	en
dc.subject.other	Wave instability	en
dc.title	Non-Boussinesq stability analysis of natural-convection gaseous flow on inclined hot plates	en
dc.type	research article	*
dc.type.hasVersion	AM	*
dspace.entity.type	Publication