arXiv subjects
Publications and source records attributed to Joachim Naumann.
This paper is concerned with weak solutions (e,h) in L^2 x L^2 of the Maxwell equations with nonlinear Ohm law and under perfect conductor boundary conditions. These solutions are defined in terms of integral identities with appropriate test functions. The main result of our paper is an energy equality that holds for any weak solution (e,h).
This paper is concerned with Kolmogorov's two-equation model for the free turbulence in three dimensions. We first discuss scaling laws for slightly more general two-equation models to highlight the special role of the model devised by Kolmogorov in 1942. The main part of the paper consists in proving the existence of weak solutions of Kolmogorov's under space-periodic boundary conditions in a cube. To this end, we provide new a priori estimates and invoke existence result for pseudo-monotone operators.
This paper is concerned with weak solutions {e,h} in L^2 x L^2 of the time-dependent Maxwell equations. We show that these solutions obey an energy equality. Our method of proof is based on the approximation of {e,h} by its Steklov mean with respect to time t. This approximation technique is well-known for establishing integral estimates for weak solutions of parabolic equations. In addition we prove the uniqueness of {e,h}.
We prove the existence of weak solutions to an unsteady thermistor system with p-Laplacian type equation for the electrostatic potential, where the electrical conductivity of the thermistor material is a monotone function of the electric field density.
We consider an unsteady thermistor system with a p-Laplace type equation for the electrostatic potential.