In order to determine some optimal (or near optimal) horizontal arrangement of vertical axis cross-flow marine current turbines within hydropower farms, an innovative, simplified, 2D numerical model was developed. It is based on the interaction between incident flow and turbine blades and was implemented in COMSOL Multiphysics. The new approach proved to save a lot of computational effort: it couples a macroscopic non-rotational 2D model of the turbine with a RANS calculation, using the k ?? turbulence model in Rotating Machinery, Transient Analysis. The study pointed on the Achard turbine, a new French concept of vertical axis cross-flow turbine. Power coefficients (turbine efficiency) were calculated for different spatial arrangements of Achard turbines within a power farm.
