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ARTICLE
ANALYSIS OF CHAOTIC NATURAL CONVECTION IN A TALL RECTANGULAR CAVITY WITH NON-ISOTHERMAL WALLS
Heather Dillona
, Ashley Emeryb,†
, Ann Mescherb
a Dept of Mechanical Engineering, University of Portland, Portland, Oregon, 97203, USA
b Dept of Mechanical Engineering, University of Washington, Seattle, Washington, 98105, USA
† Corresponding author. Email: emery@u.washington.edu
Frontiers in Heat and Mass Transfer 2013, 4(2), 1-9. https://doi.org/10.5098/hmt.v4.2.3004
Abstract
A computational model is presented that extends prior work on unsteady natural convection in a tall rectangular cavity with aspect ratio 10 and
applies Proper Orthogonal Decomposition to the results. The solution to the weakly compressible Navier-Stokes equation is computed for a range of
Rayleigh numbers between 2 × 10
7
and 2.2 × 10
8 with Prandtl number 0.71. A detailed spectral analysis shows dynamic system behavior beyond
the Hopf bifurcation that was not previously observed. The wider Rayleigh range reveals new dynamic system behavior for the rectangular geometry,
specifically a return to a stable oscillatory behavior that was not predicted in prior work. Proper Orthogonal Decomposition (POD) has been used to
analyze the computational results. Five eigenvalue modes were required to capture correctly the basic flow structure. The POD failed to capture subtle
aspects of the flow structure at high Rayleigh numbers for the model, indicating that a POD and Galerkin projection for several Rayleigh numbers will
be needed to reproduce the complex behavior of the system.
Keywords
Cite This Article
Dillon, H. (2013). ANALYSIS OF CHAOTIC NATURAL CONVECTION IN A TALL RECTANGULAR CAVITY WITH NON-ISOTHERMAL WALLS.
Frontiers in Heat and Mass Transfer, 4(2), 1–9.