Section 90.—WATER WHEELS AND TURBINES.
[1686]. Simple undershot wheel.
[1687]. Breast wheel.
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[1688]. High breast wheel.
[1689]. Overshot wheel.
[1690]. Return overshot wheel.
[1691]. Internal feed re-action wheel.
[1692]. Sunk wheel, driven by air: may be used as a meter for gas or air.
[1693]. Current wheel, driven by tidal or river current.
[1694]. Flutter wheel, with high fall.
[1695]. Horizontal wheel.
[1696]. Re-action wheel, the oldest form of turbine.
[1697]. Engel’s diagonal wheel.
[1698]. Scoop wheel for raising water. See also [No. 1024].
[1699]. Wheel, with internal buckets and feed.
Note that most of these may be reversed and made into water raising machines, as [No. 1698].
[1700] to [1703]. Sections of various forms of buckets in wood and iron. No. 1703 is a ventilated bucket which allows air to escape as the water enters.
For governing speed of water wheels and turbines, see [Section 41].
[1704]. Fourneyron’s turbine, outward flow; the outer vanes are fixed, the inner ones revolve with the shaft.
[1705]. Jonval’s turbine, downward flow; either the upper or lower set is fixed.
[1706]. Swain’s turbine, inward and downward flow, with inward curved vanes or flumes.
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[1707]. Leffel’s turbine, inward and downward flow; has one outer ring of fixed vanes and two inner sets revolving, but having different angles of flow.
[1708]. Undershot jet wheel for high pressure water.
Many other forms of turbines are extant, but are mostly modifications of the above types. The best types have means of varying the angle of the vanes and areas of passages to suit varying quantities of water.