Library Subscription: Guest

ISSN Online: 2377-424X

ISBN Print: 978-1-56700-421-2

International Heat Transfer Conference 15
August, 10-15, 2014, Kyoto, Japan

Transition in a Natural Convection Boundary Layer

Get access (open in a dialog) DOI: 10.1615/IHTC15.ncv.008947
pages 5191-5200

Abstract

A previous study of the current authors has revealed that heat transfer through a heated wall can be significantly enhanced by perturbing the boundary layer flow to advance linear to non-linear transition. In the present study, the evolution and transition of the natural convection boundary layer adjacent to an isothermally heated vertical surface is revisited by means of Bicoherence analysis, which is a statistical method based on the Fourier transform to identify and quantify quadratic wave interactions. It is found that the boundary layer can be broadly classified into three regimes: a linear flow regime, a transitional regime and a non-linear flow regime. In the non-linear flow stage, the fluctuation of the number of the resonance points is noted, which indicates resonant energy shift among different resonance points that may ultimately contribute to the enhancement of heat transfer.