Comparison of different approaches tracking a wing-tip vortex

Abstract

This paper compares the performance of different grid based and grid free modelling approaches to predict the tip vortex evolution in both near and far wing wake fields. The grid based methods cover different turbulence modelling approaches, adaptive mesh refinement and the adaptive vorticity confinement (VC) method using the OpenFOAM code. Computational vortex method (CVM) coupled with the OpenFOAM simulation of the near field is utilised to properly predict the tip vortex behaviour in the far field. All simulation results are compared to results of the wind tunnel experiments conducted by Devenport et al. (1996). The comparison is based on the analysis of the vortex core parameters: the core size, the peak tangential velocity and the axial velocity deficit. Additionally, the results are compared with another numerical study by Wells (2009, 2010). It turns out that turbulence modelling plays an important role since simple one and two-equation models overpredict the turbulence intensity in the vortex core resulting in its fast decay. The potential of the adaptive VC method depends on the underlying turbulence model. Grid free vortex method shows a good potential to improve the simulation accuracy.