Source Term Modeling of Vortex Generators

Vortex generators (VGs) are effectively used to improve the performance of the wind turbine blades by means of flow control. VGs can be represented by local geometrical disturbance on the aerodynamic surfaces. This disturbance generates vortices in the streamwise direction, energizing the boundary layer and hence delaying or suppressing the flow separation. In this way, the entire flow field is reshaped. Use of Computational Fluid Dynamics (CFD) combined with the experiments is desirable to be able to find the most efficient geometrical shape of VG and the installation of it based on the flow characteristics of the problem. However, there is a challenge of using CFD for VG simulation which is the large number of grid points required to obtain an accurate solution. One of the ways to overcome this difficulty is to model the effect of VG. Therefore this thesis will investigate the ways to model a vortex generator and validate the capability of such a model to simulate the optimal VG shape and installation.

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