Block-structured flow solver for the simulation of helicopters

FLOWer

FLOWer is a legacy flow solver by DLR. It is the predecessor of the flow solvers TAU and the CFD Software by ONERA, DLR and Airbus (CODA). FLOWer solves the URANS equations on block-structured grids. In addition to the classical one- and two-equation turbulence models, DES and LES are also supported, as well as the prediction of the laminar-turbulent transition with empirical criteria. Calculations with mesh movement and deformation, overlapping meshes (Chimera/Overset) and hanging mesh nodes are possible. A unique feature of FLOWer is the implementation of spatial discretization schemes with up to fifth-order accuracy, which makes FLOWer well suited for simulations of vortical or turbulent flows. However, due to the restriction to structured grids, FLOWer can only be used for flow simulations around complex body geometries with a great deal of effort when generating the mesh.

HARTII wind tunnel rotor
Vortex field of HARTII wind tunnel rotor computed with 4th order accurate scheme in FLOWer.

Key features

  • CFD-solver for block-structured grids
  • finite volume & differences
  • up to 5th order accurate inviscid fluxes
  • SA & k-ω turbulence models
  • Large & Detached Eddy Simulations (LES/DES)
  • empirical laminar-turbulent Transition prediction
  • dual time, explicit and implicit local time stepping
  • moving grids & mesh deformation
  • overset/chimera grids, hanging grid nodes

Areas of application

In many applications, FLOWer has been surpassed by TAU. However, for some applications it still proves its viability, especially when a high efficiency and accuracy in unsteady computations are required.

FLOWer is the preferred CFD-solver for the simulation of helicopters, as FLOWer is very well suited for the prediction of blade tip vortices in the rotor downwash due to its high spatial accuracy. Combined with hybrid turbulence modeling (DES) and fluid-structure coupling to account for rotor blade motion and deformation, state-of-the-art results can be calculated. Furthermore, FLOWer is used to carry out direct numerical simulations (DNS) and large eddy simulations (LES) for basic research into active flow control.

License notice

Access to these software products can only be granted if the organisation you are representing holds a valid license or your organisation is interested in signing such a license. If either of the aforementioned two points are fulfilled please get in touch with us providing additional information. Afterwards, we will support you in getting access to our software products. Please note, that we are, in general, not signing license agreements with private individuals.

Contact

Institute of Aerodynamics and Flow Technology