Penstocks at the Ohakuri Dam, New Zealand. This article does not cite any sources. Penstocks for hydroelectric installations are normally equipped with a gate system and a surge tank. They can be a combination of many components such as anchor block, penstock design manual pdf valve, air bleed valve, and support piers depending on the application.
The term is also used in irrigation dams to refer to the channels leading to and from high-pressure sluice gates. Penstocks are also used in mine tailings dam construction. The penstock is usually situated fairly close to the center of the tailings dam and built up using penstock rings. These control the water level, letting the slimes settle out of the water. This water is then piped under the tailings dam back to the plant via a penstock pipeline.
Penstocks are often used at mill sites to control the flow of water through the mill wheel, or to pen water into a mill pool. Penstocks are commonly used in water management systems such as surface water drainage and foul water sewers. Penstocks provide a means of isolation of flows and regulates the flow of water while delivering it to waste management facilities or power plants. Penstocks are installed at the outfall from the lagoon so that in the rare event that the surface water becomes contaminated the penstock may be closed. Global penstock market growth expected to be driven by growing demand of penstock for water management systems especially for drainage water systems”. Weirs, Sluices and Penstocks – Kingcombe Aquacare”.
This page was last edited on 11 March 2018, at 15:53. This article needs additional citations for verification. A cross-flow turbine, Bánki-Michell turbine, or Ossberger turbine is a water turbine developed by the Australian Anthony Michell, the Hungarian Donát Bánki and the German Fritz Ossberger. Unlike most water turbines, which have axial or radial flows, in a cross-flow turbine the water passes through the turbine transversely, or across the turbine blades.
As with a water wheel, the water is admitted at the turbine’s edge. After passing to the inside of the runner, it leaves on the opposite side, going outward. Although the illustration shows one nozzle for simplicity, most practical cross-flow turbines have two, arranged so that the water flows do not interfere. Cross-flow turbines are often constructed as two turbines of different capacity that share the same shaft.
The turbine wheels are the same diameter, but different lengths to handle different volumes at the same pressure. The subdivided wheels are usually built with volumes in ratios of 1:2. The blade’s edges are sharpened to reduce resistance to the flow of water. The water flows first from the outside of the turbine to its inside. The regulating unit, shaped like a vane or tongue, varies the cross-section of the flow.
The water jet is directed towards the cylindrical runner by nozzle. 120 degrees,transmitting some of the water’s kinetic energy to the active cylindrical blades. The regulating device controls the flow based on the power needed, and the available water. Water admission to the two nozzles is throttled by two shaped guide vanes. These divide and direct the flow so that the water enters the runner smoothly for any width of opening.