Monday 30 Mar 2015: Effective Boundary Conditions for Semi-Open Dispersive Systems
Lyuba Chumakova - University of Edinburgh
Harrison 170 11:00-12:00
In the classical linear dispersive wave theory it is shown that
sinusoidal waves (i.e., ~ e^i(k x -omega t)) carry energy with the
group speed c_g = d omega/dk . This concept is limited to the case
where both the frequency omega(k) and the wavenumber k must be real.
On the other hand, semi-open dispersive systems allow more than just
sinusoidal solutions: they can have exponentially blowing up and/or
decaying solutions as well. In this talk I will address the
questions of what is the direction and the speed of the energy
propagation for these exponential waves. I will show how this theory
can be implemented to develop radiation boundary conditions for
semi-open dispersive systems and show an example of the an application
of this theory to the dry atmosphere.