Enhancement of the efficiency of Savonius vertical axis wind turbine with airfoil enclosure system

This study presents a series of innovative modifications to the traditional Savonius-Wind-Turbine (SWT) design, aiming to boost its performance for utilization in metropolitan areas with low wind speeds. The advancements include five key parts: (i) Integration of an Airfoil Enclosure System (AES) around the rotor to prevent wind interference with the returning blades and to accelerate airflow. (ii) Assessing the effects of gaps within the AES. (iii) Developing a new airfoil-shaped blade profile that harnesses lift and drag forces simultaneously. (iv) Implementation of a big shaft within the novel rotors to allow for the generator's installation and evaluation of its effect. (v) Investigation of the optimum vertical gap in the AES. The result of these enhancements demonstrated a remarkable increase in efficiency (CP=0.3) by a factor of 2.3 versus the conventional/traditional SWT design (CP=0.13). This significant improvement was achieved with a three-bladed rotor featuring a novel airfoil-shaped blade profile, a 60 mm rotor shaft, and the AES containing a 100 mm vertical gap.