ISSN Online: 2377-424X
ISBN Print: 0-89116-909-1
International Heat Transfer Conference 9
A COMPARISON OF TURBULENCE MODELING PREDICTIONS TO EXPERIMENTAL MEASUREMENTS FOR HIGH RAYLEIGH NUMBER NATURAL CONVECTION IN ENCLOSURES
Аннотация
A numerical and experimental study of high Rayleigh number natural convection in an enclosure was conducted. A water-filled rectangular test cell was used, with opposing vertical walls heated and cooled isothermally, and all other walls thermally insulated. The height-to-width aspect ratio of the cell was 10.0 and the Rayleigh number based on height was 8.79 × 1010. Within this cell, regions of laminar, transitional, and turbulent flow were found. Detailed measurements of mean velocity were obtained with laser-Doppler anemometry and mean and rms fluid temperature measurements were made with fine-wire thermocouples.
A multilevel-multigrid scheme with a PISO solution algorithm was used to numerically predict the flow. Two variations of low-Reynolds number к −ε turbulence models were tested. The primary difference between the models was the treatment of the г boundary condition. Although the magnitudes of the effects of turbulence were generally over-predicted with one model and under-predicted with the other, both models predicted the locations of the laminar and turbulent flow regions reasonably well.
A multilevel-multigrid scheme with a PISO solution algorithm was used to numerically predict the flow. Two variations of low-Reynolds number к −ε turbulence models were tested. The primary difference between the models was the treatment of the г boundary condition. Although the magnitudes of the effects of turbulence were generally over-predicted with one model and under-predicted with the other, both models predicted the locations of the laminar and turbulent flow regions reasonably well.