Statistical Analysis on The Near-Wake Region of RANS Turbulence Closure Models for Vertical Axis Tidal Turbine

The flow field in the near wake region (up to six turbine diameters downstream) of a tidal current is strongly driven by combined device support structure and rotor. Accurate characterisation near-wake important, but it dominated highly turbulent, slow-moving fluid. At present, limited number research has been undertaken into for Vertical Axis Tidal Turbine (VATT) using Reynolds Averaged Navier Stokes (RANS) model shallow water environment Malaysia. This paper presents comprehensive statistical analysis Mean Absolute Error (MEA), Squared (MSE) Root (RMSE) on application comparing numerical solutions (i.e., different types RANS turbulence models Ansys Fluent) with published experimental data. Seven single VATT, represented cylindrical object, were employed preliminary study. performed this study essential exploring giving detailed understanding most suitable be improved, specifically its region. In study, defined as D ≤ 6, where diameter. shows that are unable accurately replicate based large errors computed. average RMSE at z/D = [2, 3, 4, 6] 0.5864, 0.4127, 0.4344 0.3577 while far-wake [8, 12] 0.2269 0.1590, z distance from object along length domain. error values found decrease increasing downstream object. Notably, standard k–ε realizable two best turbulent representing modelling, yielding lowest (RMSE 0.5666, 0.4020, 0.4113 0.3455) among tested parameters