Reverse Engineering for the Rotor Blades of a Horizontal Axis Micro-hydrokinetic Turbine

The geometric data for a broken blade of a horizontal axis micro-hydrokinetic turbine were obtained by reverse engineering and, reconstructed model was validated by re-engineering process and experiment. A direct scanning procedure was applied in order to verify the blade profile and stagger angles. Two computation methods were used in order to validate technical data of the turbine. For the first was used the classical computation method and, for the second method, the principle of extraction the maximum power from the fluid flow was considered. Differences for stagger angles of the blades were found, and an increased hydraulic power of 7%, when using the second design method comparing to the initial data. After re-engineering, the new runner was manufactured by a rapid prototyping method and was tested for data validation. Experiments confirmed the theoretical results with a good precision. Increased hydraulic power by 5% was recorded.