Lothar Nannen

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A construction of prismatic Hardy space infinite elements to discretize wave equations on unbounded domains Ω in H loc(Ω), Hloc(curl; Ω) and Hloc(div; Ω) is presented. As our motivation is to solve Maxwell’s equations we take care that these infinite elements fit into the discrete de Rham diagram, i.e. they span discrete spaces, which together with the(More)
The theoretical framework of the method is the so called pole condition, which characterizes radiating solutions via the poles or singularities of the Laplace transformed solutions: The Laplace transform in radial direction of an outgoing wave belongs to a certain Hardy space of holomorphic functions, while the Laplace transform of an incoming wave does(More)
A relevant difference between (9) and least squares formulations is that the former can be used to prove k-explicit stability bounds on u, while the seconds requires these bounds to be well-posed. We note that, using an appropriate operator T : V → V , any well-posed formulation in the form (2) can be translated in a sign-definite one: aT (u, v) := a(u, T(More)
We consider time harmonic wave equations in cylindrical wave-guides with physical solutions forwhich the signs of group andphasevelocities differ. Theperfectly matched layer methods select modes with positive phase velocity, and hence they yield stable, but unphysical solutions for such problems. We derive an infinite element method for a physically correct(More)
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