Hydro Turbine Selector: Head, Flow & Specific Speed

Choosing which turbine goes into a hydropower plant is not a matter of taste — it falls out of a single dimensionless number, the specific speed Ns, computed from a site's head, its available flow, and the runner's rotational speed. This simulator lets you dial in a real head and flow rate, watch Ns update live, and see the physically appropriate runner spin up in 3D: a free-spinning Pelton wheel struck by needle-valve jets for very high head and low flow, a radial-axial Francis runner for the broad middle ground most real dams occupy, or an adjustable-pitch Kaplan propeller for low-head, high-flow run-of-river sites. Switch to manual mode to force a mismatched turbine onto a site and watch the efficiency penalty appear exactly as it would on a real project.