Simulation of Complex Turbulent Flows — Drag Reduction by Dimples

Detailed numerical investigations of complex turbulent flows became feasible by high–performance computers and advanced simulation techniques such as direct numerical simulations (DNS), large–eddy simulation (LES) and hybrid LES–RANS methods (e.g. DES). For that purpose the Navier–Stokes solver LESOCC was steadily enhanced and extended at the Institute of Fluid Mechanics (LSTM), University of Erlangen– Nürnberg.

Presently the software package LESOCC contains the following features:

  • Navier–Stokes solver for incompressible fluids based on a 3–D finite–volume approach using block–structured, curvilinear body– fitted grids
  • Spatial discretization using five different schemes (second–order accurate)
  • Temporal discretization of second–order accuracy using a predictor– corrector method based on a low–storage Runge–Kutta scheme
  • Variety of different subgrid–scale and wall models
  • Two–phase flow predictions based on an Euler–Lagrange approach
  • Highly vectorized code; more than 50 % of the peak performance on vector computers
  • Parallelized by domain decomposition and explicit message passing based on MPI

LESOCC is applied in various scientific and engineering disciplines such as

  • aerodynamics, hydrodynamics and turbulence research
  • mechanical and civil engineering
  • chemical and process engineering

In the framework of the present project, numerical simulations for internal turbulent flows are carried out in order to investigate the influence of surface structures called “dimples“ on the friction drag. Drag reduction techniques such as riblets or polymers are known for a long time and of huge importance for economics. The dimple technology, however, is quite new and not understood at all. Hence, the task of the project is to shed some light into this ascinating topic in order to clarify the underlying physical mechanism.



Priv.–Doz. Dr.–Ing. Michael Breuer
Lehrstuhl für Strömungsmechanik,
Universität Erlangen-Nürnberg

Dipl.–Ing. Thomas Zeiser
Regionales Rechenzentrum Erlangen,
Universität Erlangen–Nürnberg

Dr.–Ing. Peter Lammers
Universität Stuttgart
E-Mail: email address Peter Lammers