We discuss the stabilization of the inverse cascade in the large-scale instability of the Kolmogorov flow described by the complete CahnHilliard equation with inclusion of Beta effect, large-scale friction and deformation radius. The friction and the Beta values halting the inverse cascade at the various possible intermediate states are calculated by means of singular perturbation techniques and compared to the values resulting from numerical simulation of the complete CahnHilliard equation. The excellent agreement validates the theory. Our main result is that the critical values of friction or Beta halting the inverse cascade scale exponentially as a function of the jet separation in the final flow, contrary to previous theories and phenomenological approach.
Dispersive and friction-induced stabilization of the Cahn-Hiliard inverse cascade
2003
Abstract
We discuss the stabilization of the inverse cascade in the large-scale instability of the Kolmogorov flow described by the complete CahnHilliard equation with inclusion of Beta effect, large-scale friction and deformation radius. The friction and the Beta values halting the inverse cascade at the various possible intermediate states are calculated by means of singular perturbation techniques and compared to the values resulting from numerical simulation of the complete CahnHilliard equation. The excellent agreement validates the theory. Our main result is that the critical values of friction or Beta halting the inverse cascade scale exponentially as a function of the jet separation in the final flow, contrary to previous theories and phenomenological approach.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
