Prediction of the Wake Behind a Horizontal Axis Tidal Turbine Using a LES-ALM
A large-eddy simulation-actuator line method (LES-ALM) applied to a single horizontal axis tidal turbine is presented and validated against experimental data. At a reasonable computational cost, the LES-ALM is capable of capturing the complex wake dynamics, such as tip vortices, despite not explicitly resolving the turbine’s geometry. The LES-ALM is employed to replicate the wake behind a laboratory-scale horizontal axis turbine and achieves a reasonably good agreement with measured data in terms of streamwise velocities and turbulence intensity. The turbine is simulated at six tip speed ratios in order to investigate the rate of decay of velocity deficit and turbulent kinetic energy. In the far-wake, these quantities follow a similar decay rate as proposed in the literature with a −3/4 slope. For cases when the turbine spins at or above the optimal tip speed ratio, the levels of turbulent kinetic energy and wake deficit in the far-wake are found to converge to similar values which seem to be linearly correlated. Finally, transverse velocity profiles from the simulations agree well with those from an analytical model suggesting that the LES-ALM is well-suited for the simulation of the wake of tidal stream turbines.
The authors would like to acknowledge the support of the Supercomputing Wales project, which is part-funded by the European Regional Development Fund (ERDF) via the Welsh Government.
- 5.Munters W, Meyers J (2018) Dynamic strategies for yaw and induction control of wind farms based on large-eddy simulation and optimization. Energies 11(1):177Google Scholar
- 6.Ouro P, Stoesser T, Fraga B, Lopez-Novoa U (2018) Hydro3DGoogle Scholar
- 11.Martínez-Tossas LA, Churchfield MJ, Yilmaz AE, Sarlak H, Johnson PL, Sørensen JN, Meyers J, Meneveau C (2018) Comparison of four large-eddy simulation research codes and effects of model coefficient and inflow turbulence in actuator-line-based wind turbine modeling. J Renew Sustain Energy 10(3), 033301CrossRefGoogle Scholar