Influence of Confined Channel on the Self-Starting Capability of Twin Counter-Rotating Savonius Hydrokinetic Turbines in Tandem Arrangement

Hildan Fahrizal Nur Faurizki (Mechanical Engineering Department, Politeknik Negeri Semarang, Tembalang, Semarang 50275, Indonesia)
Tri Yogi Yuwono (Mechanical Engineering Department, ITS, Sukolilo, Surabaya 60111, Indonesia)
Savitri Ramadhani (Mechanical Engineering Department, Politeknik Negeri Semarang, Tembalang, Semarang 50275, Indonesia)
Vena Rizky Pusparani (Politeknik Perkapalan Negeri Surabaya, Sukolilo, Surabaya 60111, Indonesia)
Anisah Nurul Izzah (Mechanical Engineering Department, Universitas Pembangunan Nasional Veteran Jawa Timur, Surabaya 60294, Indonesia)
Chezta Ahmad Muzakky (Politeknik Perkapalan Negeri Surabaya, Sukolilo, Surabaya 60111, Indonesia)
Muhammad Fiky Izzulhaq (Politeknik Perkapalan Negeri Surabaya, Sukolilo, Surabaya 60111, Indonesia)

JMES: The International Journal of Mechanical Engineering and Sciences
Vol 10 No 2 (2026)

This research aims to improve Savonius turbine’s self-starting capability by increasing the static torque coefficient using several methods. In this research, a channel is involved and an additional turbine is applied to optimize the energy harvested from hydropower using numerical approach. To solve the governing equations, - Realizable with Enhanced Wall Treatment as the turbulent model and Coupled algorithm as the solver are deployed. Through 0.61, 0.45, 0.3, 0.22, 0.1, 0.05 blockage levels and 2.667D and 60D distances, the optimum self-starting condition is obtained at 0.61 and 0.45 blockage levels for 2.667D upstream and downstream turbines. The upstream and downstream turbines share a similar self-starting capability, with an increase as well as an increase of blockage at 60D.