Performance of a Savonius vertical axis wind turbine installed on a forward facing step

Abstract

This study investigates the effects of installing a Savonius turbine on a forward-facing step to increase the power efficiency. Since the flow is disturbed by the step, the turbine may benefit from the accelerated flow found on top of the step. The flow field is solved using computational fluid dynamics in a 3D computational domain. The finite volume method is used to solve the Reynolds average Navier–Stokes governing equations and the SST k-ω turbulence equations. This simulation includes both rotating turbine and the step. The novelty of this work is to study this configuration with a power law wind velocity distribution as inlet velocity, which is more realistic in common applications, and to investigate a different turbine. The study shows that the Savonius turbine generates up to 73% more power when installed on a 5 m step. However, in case of a very high step, or a different turbine no improvement has been observed.