Abo Bibliothek: Guest

ISSN Online: 2377-424X

ISBN Print: 0-89116-909-1

International Heat Transfer Conference 9
August, 19-24, 1990 , Jerusalem, Israel

INVESTIGATION OF THE ROUTE TO TURBULENCE IN A DIFFERENTIALLY HEATED CAVITY

Get access (open in a dialog) DOI: 10.1615/IHTC9.2410
pages 417-422

Abstrakt

We numerically and experimentally investigate the route to turbulence in a vertical differentially heated air-filled cavity of height 0.36m and of aspect ratio 4. Experimental observations and numerical predictions resulting from integration of the 2-D Boussinesq equations quantitatively agree on the appearance of the high frequency (≈ 0.8 Hz) travelling wave instability and on the appearance of another frequency (≈ 0.25 Hz) at larger values of the temperature difference. However, the experimental data show an unsteady phenomenon of low frequency (≈ 0.02 Hz) which is not found is the 2-D numerical simulations nor in the 3-D simulations in which periodicity in the direction orthogonal to the base flow plane is assumed. On the other hand, these 3-D computations show that the 2-D solutions are first unstable to a 3-D steady instability. This instability is however very weak and affects very little the onset of the 2-D travelling wave instability.