[home] [Personal Program] [Help]

---

Session: Control 3
Session starts: Wednesday 26 August, 10:30
Presentation starts: 10:30
Room: Room D

---

André Fuchs (ForWind, Institute of Physics, University of Oldenburg, Oldenburg, Germany)
Wided Medjroubi (ForWind, Institute of Physics, University of Oldenburg, Oldenburg, Germany)
Nico Reinke (ForWind, Institute of Physics, University of Oldenburg, Oldenburg, Germany)
Gerd Guelker (ForWind, Institute of Physics, University of Oldenburg, Oldenburg, Germany)
Joachim Peinke (ForWind, Institute of Physics, University of Oldenburg, Oldenburg, Germany)

Abstract:
Fractal grids generate turbulence by directly exciting many length-scales of different sizes simultaneously, rather than using the nonlinear cascade mechanism to obtain multiscale excitation, as it is the case for classical grids. These scales influence each other and show very different properties compared to all previously documented turbulent flows. In this work we present experimental wind tunnel and computer fluid dynamics (CFD) studies of the turbulent flow generated by a fractal grid under the same conditions. We did an extensive statistical study and a direct comparison between the experimentally and numerically acquired time series in order to investigate and compare one-point- and two-point-statistics. In addition we present an application of a stochastic method, so-called Langevin approach, to the experimentally and numerically acquired velocity increment time series to examine three-point-statistics in terms of Kramers-Moyal coefficients.