Talk:Francis turbine

misstatement concerning water wheels
The article says "water wheels are inefficient" which is an overstatement that distorts historical fact. Early undershot waterwheels were grossly inefficient, usually less than 30%, but the later period overshot and backshot steel Fitz wheels and the Poncelet wheel have efficiencies comparable with the Francis turbine at considerably lower cost of manufacture. Unfortunately these innovations came after the turbine revolution, industrialists were not yet concerned about the excessive fish kill of bladed turbines, and (in the case of the Fitz wheels) costs of impoundment and diversion to a wheel are higher, so those designs were not widely adopted and have only recently re-entered production for environmental reasons. The Poncelet wheel is very nearly a turbine set sideways, although obviously it does not have axial flow like a Francis turbine. —Preceding unsigned comment added by 205.153.180.229 (talk) 13:33, 24 March 2011 (UTC)

Vertical-shaft question
thanks for giving me a chance to grow myself,I've a question about vertical shaft turbine that is there any loss in the velocity of water flow through turbine blades when the motion is just horizontal as compared to vertical in horizontal shaft turbine pls clear my topic(lalit gandhi)>(27-may-2011) — Preceding unsigned comment added by Lalit gandhi (talk • contribs) 05:39, 27 May 2011 (UTC)

Water head
While the articles states (with no source given) that Francis turbines operate in a water head from 40 to 600 m, I think this just holds for large installations. On a Czech website dedicated to small hydroelectric power plants the head is given as 2 to 8 meters (for horizontal axis turbine) and 0,5 to 5 metres (for vertical axis turbine) . --Jvs (talk) 08:19, 4 September 2016 (UTC)
 * Jvs: Free feel to fix it yourself if you can add reliable sources. In my opinion, a technical book about water turbine design would be the ideal source. I would say that a website about a water turbine manufacturer is not a reliable source, but it is still better that nothing. Mario Castelán Castro (talk) 13:42, 4 September 2016 (UTC).

Blade efficiency & Degree of reaction
What is the point of these sections? A load of equations and diagrams with no attempt to explain what any of the terms mean and no links to other articles which might help explain it. Yet another typically badly written technical Wikipedia article which seems aimed at those who already know rather than enlightening anyone who doesn't. 130.246.57.110 (talk) 08:32, 13 October 2022 (UTC)