dorsal/arxiv
View SchemaStability of flow through a slowly diverging pipe
| Authors | Kirti Chandra Sahu, Rama Govindarajan |
|---|---|
| Categories | |
| ArXiv ID | physics/0409037 |
| URL | https://arxiv.org/abs/physics/0409037 |
| Journal | Journal of Fluid Mechanics 531 (2005) 325-334 |
Abstract
Although the critical Reynolds number for linear instability of the laminar flow in a straight pipe is infinite, we show that it is finite for a divergent pipe, and approaches infinity as the inverse of the divergence angle. The velocity profile at the threshold of inviscid stability is obtained. A non-parallel analysis yields linear instability at surprisingly low Reynolds numbers, of about 150 for a divergence of 3 degrees, which would suggest a role for such instabilities in the transition to turbulence. A multigrid Poisson equation solver is employed for the basic flow, and an extended eigenvalue method for the partial differential equations describing the stability.
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"abstract": "Although the critical Reynolds number for linear instability of the laminar\nflow in a straight pipe is infinite, we show that it is finite for a divergent\npipe, and approaches infinity as the inverse of the divergence angle. The\nvelocity profile at the threshold of inviscid stability is obtained. A\nnon-parallel analysis yields linear instability at surprisingly low Reynolds\nnumbers, of about 150 for a divergence of 3 degrees, which would suggest a role\nfor such instabilities in the transition to turbulence. A multigrid Poisson\nequation solver is employed for the basic flow, and an extended eigenvalue\nmethod for the partial differential equations describing the stability.",
"arxiv_id": "physics/0409037",
"authors": [
"Kirti Chandra Sahu",
"Rama Govindarajan"
],
"categories": [
"physics.flu-dyn"
],
"journal_ref": "Journal of Fluid Mechanics 531 (2005) 325-334",
"title": "Stability of flow through a slowly diverging pipe",
"url": "https://arxiv.org/abs/physics/0409037"
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