Jonval turbine

The Jonval turbine is a water turbine design invented in France in 1843, in which water descends through fixed curved guide vanes which direct the flow sideways onto curved vanes on the runner. It is named after Feu Jonval, who invented it. The Jonval incorporated ideas from European mathematicians and engineers, including the use of curved blades, which gave it triple the efficiency of a water wheel. This new turbine failed to satisfy the public interest in seeing the water wheels in action, which was likely accepted as a minor drawback at that time.