Автор |
Shepherd, Theodore G. |
Дата выпуска |
1988 |
dc.description |
A novel method is presented for obtaining rigorous upper bounds on the finite-amplitude growth of instabilities to parallel shear flows on the beta-plane. The method relies on the existence of finite-amplitude Liapunov (normed) stability theorems, due to Arnolʼd, which are nonlinear generalizations of the classical stability theorems of Rayleigh and Fjørtoft. Briefly, the idea is to use the finite-amplitude stability theorems to constrain the evolution of unstable flows in terms of their proximity to a stable flow. Two classes of general bounds are derived, and various examples are considered. It is also shown that, for a certain kind of forced-dissipative problem with dissipation proportional to vorticity, the finite-amplitude stability theorems (which were originally derived for inviscid, unforced flow) remain valid (though they are no longer strictly Liapunov); the saturation bounds therefore continue to hold under these conditions. |
Издатель |
Cambridge University Press |
Название |
Rigorous bounds on the nonlinear saturation of instabilities to parallel shear flowsWith an appendix by P. H. Haynes. |
DOI |
10.1017/S002211208800271X |
Electronic ISSN |
1469-7645 |
Print ISSN |
0022-1120 |
Журнал |
Journal of Fluid Mechanics |
Том |
196 |
Первая страница |
291 |
Последняя страница |
322 |
Аффилиация |
Shepherd Theodore G.; University of Cambridge; |