Natural Convection in Wide Spherical Shells
Abstract We have studied the problem of natural convection in wide spherical shells both experimentally and numerically, and find that there are critical Rayleigh numbers at which the convection changes in fundamental ways. For sufficiently low Ra the convection is steady, but above a certain value...
| Published in: | PAMM |
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| Main Authors: | , , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Wiley
2003
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| Subjects: | |
| Online Access: | http://dx.doi.org/10.1002/pamm.200310463 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fpamm.200310463 https://onlinelibrary.wiley.com/doi/pdf/10.1002/pamm.200310463 |
| Summary: | Abstract We have studied the problem of natural convection in wide spherical shells both experimentally and numerically, and find that there are critical Rayleigh numbers at which the convection changes in fundamental ways. For sufficiently low Ra the convection is steady, but above a certain value it becomes time‐dependent, with plumes dripping off the south pole in distinct pulses. For higher values still these convective pulses become irregular in time. The experimental results show though that even at these very high Rayleigh numbers the convection remains purely axisymmetric. A two‐dimensional numerical code is therefore used to study these flows in more detail, and reveals the same transition from steady to periodic to chaotic behavior. Finally, the dependence of the critical Rayleigh number and the period on the Prandtl number are explored. |
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