EXPERIMENTAL STUDY OF CONVENTIONAL SAVONIUS WIND TURBINES USING RECTANGULAR VALVE-AUGMENTATION

• Main Author: Ihsan, Muhammad
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/70306
• Institution: Institut Teknologi Bandung

<p align="justify">The Savonius wind turbine is preferable for a micro-scale application due to its simple design, omnidirectional wind, and good self-starting ability. However, the main disadvantage of a Savonius wind turbine is its low coefficient of power (CP) caused by the negative torque from the returning blade. Earlier research has proved that circular valve augmentation on a Savonius wind improves the CP. Therefore, this final project experimentally investigated the performance of the conventional Savonius rotor augmented with a rectangular check valve (CV) using different valve aspect ratio (VAR) and opening area ratio (OAR). Experiments were conducted at wind speeds of 6.2 m/s and 8.45 m/s using VAR variations of 1:1, 2:1, 3:1, 4:1, and 5:1. The VAR that gave the optimal performance for each wind speed was then chosen for the OAR variation experiment, which used 0.95%, 1.90%, and 2.85% OAR variations. The collected data were then processed to produce plots for CP, coefficient of dynamic torque (Ct), and coefficient of static torque (Cts) to evaluate the rotor’s performance. The 2:1 VAR had the highest maximum CP at 6.2 m/s, and at 8.45 m/s, it was the 3:1 VAR that achieved it. The 2:1 and 3:1 VAR’s maximum CP was a 6.99% and 6.76% improvement to the non-valved rotors, respectively. The Ct performance of both VARs showed a similar trend to the CP performance. There was no notable change to the maximum Cts of all VAR rotors. However, the VAR rotors significantly changed the negative Cts values. The 2.85% OAR of both 2:1 and 3:1 VAR gave the biggest maximum CP decrease compared to the 0.95% OAR, which was -2.01% and -1.81%, respectively. The Ct performance of the OAR rotors showed a similar trend to the CP performance. There was no noticeable change in the Cts performance of the OAR rotors of the 2:1 VAR. However, the 0.95% OAR of the 3:1 VAR rotor gave a better Cts performance than the 1.90% and 2.85% OARs.