
Jim Denier
School of Mathematical Sciences, University of Adelaide
Anomalous behaviour in boundarylayers: shortscale instabilities, finite distance breakdown and nonuniqueness
Wednesday 24th September 14:0514:55pm,
Eastern Avenue Lecture Theatre.
This talk will present some new results on an old problem of (very) shortscale instabilities in boundarylayer flows.
Starting with a rather simple flow over a heated surface we can show that the boundarylayer equations predict an anomalous
short scale instability that is independent of the Reynolds number, a nondimensional parameter that defines the dynamics of our fluid system.
The origin of this short scale instability is explored and shown to be linked to a finite distance singularity which arises in the
boundarylayer equations. We'll then go on to show that this singularity occurs in a wide range of boundarylayer problems
and attempt (but perhaps fail) to argue that it is nonphysical by presenting some calculations from a full numerical solution of the NavierStokes equations.







