Tailored Vortex Systems

Motivation


Vortices are a consequence of lift produced by an aircraft. In the context of aircraft design there are two major aspects which need to be regarded:

  • Vortices pose a threat to following aircraft. In order to alleviate vortices methods for reducing their energy, adding turbulence, or triggering inherent instabilities are the options.
  • The vortices' energy is directly related to the amount of induced drag of the aircraft. In order to achieve profitable gains in performance methods for optimizing lift distribution or wing-tip design come into play.

 

 


Overall Objective

Vortices need to be understood as a powerful hazard but also as an interesting opportunity in an innovative air-transport system.

At ILR Tailored Vortex Systems is a scientific concept which aims at an in-depth understanding of the vortex structure. The objective is to gain control of parameters that influence performance as well as instability and stability of the vortex - e.g. the core axial velocity component.

 

 

 

Methods


Wing-tip's impact on the axial velocity inside the vortex core Vortex intensity produces "jets", turbulence produces "wakes".

A close coupling between experimental and numerical methods is necessary:

Experimental methods comprise:

  • Particle Image Velocimetry for high-resolution of velocity-fields
  • Hot-wire anemometry for quantifying turbulent and frequency-based characteristics
  • Several visualization methods in order to gain insight into predominant flow behavior

Numerical methods comprise:

  • Hybrid mesh generation with Centaur gird generator
  • DLR-TAU flow solver with Reynolds-Stress-Turbulence-Modeling in order to gain a physical correct simulation of vortex roll-up process

Current Work Packages

  • Investigate the influence of systematic variation of the wing-tip geometry on the vortex structure
  • Investigate the role of axial velocity in the vortex on performance and stability
  • Investigate perturbations in collapsing vortices