Wind energy evaluation for a highly complex terrain using Computational Fluid Dynamics (CFD)

Computational Fluid Dynamics (CFD) modeling is becoming an important tool in the wind industry to study wind flow patterns. Accurate CFD simulations of wind flow are essential for the selection of wind farm locations as well as the design of appropriate wind turbines. This article validates the average wind power estimated by the state of the art CFD tool WindSim using on-site measurements from nine meteorological stations scattered around a highly complex terrain at several heights. It is known that the numerical solver is very sensitive to the wide number of computational parameters that have to be taken into consideration by the user. This paper investigates those computational parameters in details including a grid dependency test, the order of the discretization schemes, the turbulence models (Standard k-ε, k-ε with Yap corrections, RNG k-ε and Modified k-ε) and the iterative convergence criteria. The best model is employed to investigate major hot spots identified where wind farming is feasible in Mauritius with due consideration to land use and topographical requirements. Wind maps are produced at four levels which are of typical hub heights of commercial wind turbines. These maps can be used to assist in the decision-making process when locating best placements for wind farming.