HR: 1340h
AN: U43B-1136 [Abstracts]
TI: Spontaneously Emergent Marginally Stable Highly Non-normal Jets in Turbulent Flows
AU: * Farrell, B
EM: farrell@seas.harvard.edu
AF: Harvard University, 24 Oxford Street, Cambridge, MA 02138, United States
AU: Ioannou, P
EM: pji@seas.harvard.edu
AF: University of Athens, Panepistimiopolis, Zografou, Athens, 157 84, Greece
AB:
A remarkable phenomenon in turbulent flows is the spontaneous emergence of coherent large
spatial scale jets. Familiar geophysical examples of this phenomenon include the Jovian
banded winds and the Earth's polar front jet. These jets are maintained in a nonlinear equilibrium with the much
smaller spatial and temporal scale turbulence with which they coexist. Frequently these jets are found to exist in
marginally stable
states that support large transient growth. In this talk a comprehensive theory for the interaction of jets with
turbulence,
stochastic structural stability theory
(hereafter SSST), is introduced and applied to the problem of understanding the formation and maintenance in
turbulent flows of marginally
stable but highly non-normal equilibrium jets.
DE: 3215 Instability analysis
DE: 3265 Stochastic processes (3235, 4468, 4475, 7857)
DE: 4435 Emergent phenomena
DE: 4485 Self-organization
DE: 4490 Turbulence (3379, 4568, 7863)
SC: Union [U]
MN: 2007 Fall Meeting