“…Several examples of Francis turbine runner optimization exist (Enomoto, Kurosawa, & Kawajiri, 2012;Nakamura & Kurosawa, 2009;Pilev et al, 2012), some even optimizing the runner and draft tube simultaneously (Lyutov, Chirkov, Skorospelov, Turuk, & Cherny, 2015). Most of these attempts deal with medium-to-high specific speed Francis turbines, but other turbine types have also been optimized using similar techniques (Ezhilsabareesh, Rhee, & Samad, 2018;Semenova et al, 2014).…”