2022-01-22T08:31:15Z
https://meral.edu.mm/oai
oai:meral.edu.mm:recid/771
2021-12-13T00:07:04Z
1582963739756:1582967046255
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Local instability of a rotating flow driven by precession of arbitrary frequency
Me Me Naing
Fukumoto, Yasuhide
We revisit the local stability, to three-dimensional disturbances, of rotating flows with circular streamlines, whose rotation axis executes constant precessional motion about an axis perpendicular to itself. In the rotating frame, the basic flow is steady velocity field linear in coordinates in an unbounded domain constructed by Kerswell (1993Geophys. Astrophys. Fluid Dyn.72 107–44), and admits the use of the Wentzel–Kramers–Brillouin (WKB) method. For a small precession frequency, we recover Kerswell’s result. A novel instability is found at a large frequency for which the axial wavenumber executes an oscillation around zero; significant growth of the disturbance amplitude occurs in a very short time interval only around the time when the axial wavenumber vanishes. In the limit of infinite precession frequency, the growth rate exhibits singular behavior with respect to a parameter characterizing the tilting angle of the wave vector. (Some figures in this article are in colour only in the electronic version)
2011
http://hdl.handle.net/20.500.12678/0000000771
https://meral.edu.mm/records/771