Natural convection in a horizontal concentric cylindrical annulus: oscillatory flow and transition to chaos

Abstract

An experimental study of transition from steady laminar to chaotic flow in a horizontal annulus between concentric cylinders is conducted for 0.90×105[les ]RaL[les ]3.37×105. Qualitative information on the averaged thermal field is obtained by an interferometric method, whereas the kinematics are visualized by using smoke lines. The transition from steady to unsteady mono- and multi-periodic regimes is accurately studied by a CTA and CCA combined hot-wire technique. Different data analyses are performed in order to differentiate the forms of transition.

Large-eddy simulation of transition to turbulence in natural convection in a horizontal annular cavity

“…Numerical results of the present work are in agreement with experimental observations of Powe et al [44], Bishop et al [45], Kuehn and Goldstein [7], Labonia and Guj [9] and with the sketch about the structure of the flow, present by McLeod and Bishop [8]. It is important to empathize that, as shown in Fig.…”

“…Later, other investigations [2][3][4] were done in order to study the effect of different parameters on the local and overall heat transfer coefficient for several kinds of fluids. New experimental techniques allowed to obtain important informations concerning to stable and unstable flows [5][6][7][8][9]. Kuenh and Goldstein [7] studied natural convection in annular cavities filled with pressurized nitrogen over a Rayleigh number range of 2.2 Â 10 2 6 Ra 6 7.7 Â 10 7 and for g = 2.6.…”

“…They have presented sketches that show the oscillating thermal plume for Ra = 1 Â 10 7 and the dramatic changes of this structure as Ra is increased up to 10 9 . Labonia and Guj [9] have performed experiments to analyze oscillatory and transitional flows for 0.90 Â 10 5 6 Ra 6 3.37 Â 10 5 and for g = 2.36, using air at atmospheric pressure. It was verified that the mechanisms of transition to chaos have been differentiated by different dynamical indicators.…”

Appearance of quasiperiodicity within a period doubling route to chaos of a swaying thermal plume

“…Before the final transition to chaos (N II ), a relaminarisation phase is observed, consisting in a small window of periodicity (P 4 ) whose frequency is related with the fundamental frequency of the first periodic regime by a factor 4. A very thorough experimental analysis of the transition to chaos in an air-filled annulus with R = 2.36 was provided by Labonia and Guj [17]. Quantitative and qualitative measurements were performed by interferometry, smoke visualization and hot wire anemometry.…”

Three-dimensional linear stability of natural convection in horizontal concentric annuli

“…They, however, always assumed the symmetry conditions at the vertical center-plane, which might not lead to realistic solutions especially for the small aspect ratio. In fact, Labonia and Guj [9] as well as Powe et al [2] have recently performed an experimental study of the transition from steady to chaotic flow in a horizontal annulus for a small aspect ratio and showed an oscillating flow pattern passing through the vertical center-plane above a critical value.…”