Some recent results on instability of ideal plane flows
نویسندگان
چکیده
We study linear and nonlinear instability of steady incompressible inviscid flows. First, some sufficient conditions of linear instability for a class of shear flows are given. Second, nonlinear instability in the L2-norm of velocity is proved under the assumption that the growth rate exceeds half of the Liapunov exponent of the steady flow, for any bounded domain. We also estimate the growth of the semigroup generated by the linearized operator, in the Lp (p > 1) space of the velocity.
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