Selecting Francis turbines: Trends in the past 20 years

This article updates the previous “Modern trends in selecting and designing Francis turbines” and “Designing Francis turbines: trends in the last decade” articles, which were published in 1976 and 1987 respectively. The authors’ aim is to provide hydro consultants with an up-to-date pre-sizing tool for Francis turbines. This can be useful both during feasibility studies and in the preparation of technical specifications. As in previous articles, the object of the study is the sizing of the main components of the unit, such as the runner, the spiral case and the draft tube.