The rapid and low-noise strategy of Deck et al. [7] for the RANS-to-WMLES switch compatible with compressible flow solvers on curvilinear grids is presented. It can be used both as an inflow condition or as an embedded resolved turbulence injection and combines Zonal Detached Eddy Simulation, Dynamic Forcing and Zonal Immersed Boundary Conditions (...
Boundary-layer-transition computations are performed using the in-house finite-volume solvers elsA by ONERA and TAU by DLR. Reynolds-averaged Navier-Stokes simulations, using the Langtry-Menter model as well as semi-empirical transition criteria, are presented using both solvers for a rotor in climb. The numerical results are compared to temperatur...
The aim of our study is to improve the prediction of SSC in wave boundary layers by using simple analytical tools which take into account the more important involved physics, for practical use in coastal engineering. Our study will show that: - For practical applications the period-averaged eddy viscosity could be described by a simple analytical f...
We prove a universal energy estimate between the solution of the three-dimensional Lamé system on a thin clamped shell and a displacement reconstructed from the solution of the classical Koiter model. The mid-surface of the shell is an arbitrary smooth manifold with boundary. The bound of our energy estimate only involves the thickness parameter, c...
Germany
The present dissertation addresses the interfacial region between the extratropical troposphere and stratosphere (tropopause region). In the first part, climatologies of the tropopause, tropopause region, and tropopause sharpness are presented. These are based on vertically high resolved radiosonde data of altogether 95 extratropical stations. Conc...
The atmospheric boundary layer is structured vertically into several conceptual sublayers because the main airflow characteristics, e.g. the velocity field, air temperature, and air moisture, show different height dependent features. To investigate mean airflow characteristics over a Scots pine forest up to several stand heights, remote sensing and...
Germany
We investigate solutions of the two-dimensional Koiter model and of the three-dimensional linear shell model in the case where the shell is clamped and its mean surface is elliptic. For smooth data, these solutions admit multiscale expansions in powers of ε^1/2 where ε denotes the (half-)thickness of the shell. Both expansions contain terms indepen...
Germany
