Design of a Maneuvering Marine Hydrokinetic Cycloturbine

A Marine Hydrokinetic (MHK) cycloturbine is a renewable electric power generation system used in rivers or tidal environments. MHK cycloturbines have foils oriented perpendicular to the flow in a paddlewheel configuration, and use the lift from these foils to produce power. Due to the high cost associated with its operation and maintenance, it was desired to design an MHK system that can self-deploy, with propulsion and control mechanisms similar to a cyclorotor aircraft. This paper investigates different design configurations for such a vehicle, and analyzes the basic force and moment balance required. Computational Fluid Dynamics (CFD) was used to predict cycloturbine efficiency, during both power generation and maneuver. A six-DOF simulation model is being developed, where the turbine propulsive force model is matched to CFD analysis. A four turbine design with stacked counter-rotating turbines was determined to provide the best vehicle control and performance. Future experimental work includes investigation of a single small-scale crossflow turbine to validate the CFD and propulsive force model used in the six-DOF simulation.