Pelton wheel

Turbine flow meters are composed of some form of rotary device such as a helical rotor, Pelton wheel or a vane mounted in the flow stream. The fluid passing the rotor causes the rotor to turn at an angular velocity which is proportional to the flow velocity and hence the volumetric flowrate through the meter. The rotary motion of the rotor is sensed by some form of pick-up device that produces an electrical pulse output. The frequency of this signal is proportional to the flowrate and the total count of pulses is proportional to the total volume of liquid passed through the meter. 

The turbine turns a generator to produce electricity [22], A variety of turbines may be used, including a Pelton wheel for high head, low-flow water supply, or a propeller-type turbine for low-head installations [24, 25]. 

Pelletizing, in pyrometallurgy, 16 140 Pelouze reaction, 17 227 Peltier effect, 21 555 24 428 Pelton wheel turbine, 26 85 Pemanent Red 2B, Strontium Salt, pigment for plastics, 7 366t PEM fuel cell (PEMFC), 12 202-203 PEN, 10 222. See also Poly(ethylene 2,6-naphthalenedicarboxylate) (PEN) Penaeid shrimp, aquacultural chemical needs, 3 209... 

Turbines, Pelton wheels Liquids and gases 140 (See Volume 1, Section 6.3.9) Fuel metering in aircraft High repeatability. Can be used at high temperatures and pressures... 

As the jet from a nozzle is frequently employed for power purposes in a steam turbine or a Pelton wheel, we are interested in its energy efficiency. The efficiency of a nozzle is defined as the ratio of the power in the jet to the power passing a section in the pipe at the base of the nozzle. As the discharge is the same for the two points, the efficiency is merely the ratio of the heads at these two sections. Thus, referring again to the conical nozzle, e = HJH. But H2 = V2/2g, and Hr = pjw + V t2g, and so from Eq. (10.59) it follows that H2 = C2,H1. Hence the nozzle efficiency is... 

It has also been found that the efficiency of Pelton wheels can be improved by several percent by similar means, as a better nozzle design provides a jet with a more uniform velocity and one that has less tendency to disperse before it strikes the wheel. 

The permeate of the MF units is fed to two SWRO units equipped with high-pressure pumps with an energy-recovery system (Pelton wheel). The SWRO units comprise 44 pressure vessels loaded with 6 Dow/FilmTec SW30 membranes each. The designed permeate capacity of each unit is 210 m3/h per unit with a recovery of 50-5 5%. Antisealant is dosed to the feed stream of the SWRO with a concentration of 3 to 4 ppm [15]. 

Hydraulic turbines are used for recovering energy from high-pressure liquid streams. A common process application is an absorber-stripper combination. In this apphcation, a gas is absorbed in a solvent at a high pressure, where absorption is favored. Then, the solvent is stripped of the absorbed components at a low pressure, where stripping is favored, to recover the solvent. Thus, the energy of the high-pressure solvent stream from an absorber can be partially recovered by a hydraulic turbine. There are three types of hydraulic turbines, the Pelton-wheel turbine, the Francis turbine, and the propeller reaction turbine, an axial type turbine. The propeller reaction turbine is used in hydroelectric applications and will not be considered further. The Pelton-wheel and Francis tur-... 

In the Pelton-wheel turbine, used for low flow rates, a high-pressure liquid flows through a nozzle to convert the pressure to a high velocity jet which impinges on an impulse wheel or runner. This turhine may contain one to foiu nozzles. Above approximately 800 m /h (28,200 ft /h) the Francis turbine becomes... 

Switzerland, with a net head of 5330 ft. The water from this plant drives an impulse turbine (Pelton wheel) with a diameter to the middle of the blades of 10.89 ft. The wheel turns at 500 rpm [1]. What is the ratio of blade speed to jet speed for this turbine How does this compare with the optimum discussed in Sec. 7.4 I... 

Pelton wheel, polyurethane, by ESD, 4-in pitch diameter, just right for spinning permanent magnet motors or car alternators at 1,000 to 2,000 rpm for up to t4-inch water jets. Shape is a bit flat to be a true pelton action, but works quite well for the price. Has /2-inch center hole and can be drilled for attachment to a hub. 113... 

Pelton wheel, bronze, by Harris Hydro, 4-inch pitch diameter, for up to /4-inch nozzle, up to 4 nozzles. Integral hub threaded to screw onto shaft of Delco or 80-A Ford Alternator. 240. 

Impulse Turbine - A turbine that is driven by high velocity jets of water or steam from a nozzle directed to vanes or buckets attached to a wheel. (A pelton wheel is an impulse hydroturbine). 

Water Turbine - A turbine that uses water pressure to rotate its blades the primary types are the Pelton wheel, for high heads (pressure) the Francis turbine, for low to medium heads and the Kaplan for a wide range of heads. Primarily used to power an electric generator. 

Local/external alarm - once the alarm monitoring unit has detected a situation that triggers an alarm it may activate a local and external alarm. The local alarm which indicates that there is a flow in the system is commonly achieved by the use of a Pelton wheel where a small quantity of water that is flowing through the range pipes is diverted and turns a mechanical bell situated near the sprinkler control valve location. The alarm can be raised externally through an automatic link to a commercial, alarm receiving centre (ARC). 

The type of turbine chosen for any hydro scheme will depend upon the discharge rate of the water and the head of water available. A Pelton Wheel is a water turbine in which specially shaped buckets attached to the periphery of the wheel are struck by a jet of water. The kinetic energy of the water turns the wheel which is coupled to the generator. 

The Pelton wheel reduces energy by directing the hrine/concentiatc stream at full pressure into buckets on a wheel that turns a shaft. This shaft is directly connected to the high-pressme SWRO pump/motor assembly. The shaft reduces the load on the main pmnp/motor and thus lowers the energy required to drive the process. 

Figure 4.1 Pelton wheel RO flow scheme. (From Stover, 2006, p. 13.)...

Figure 4.2 Kcluie of a Pelton wheel. (From Kuendig, 2006a, p. 19.)...

Pelton wheels have been modified and improved specifically to optimize them for use with SWRO systems. This innovation has resulted in efficiency and other improvements, and Pelton wheels continue to be used with SWRO systems today. Current Pelton wheel devices have overall net transfer efficiencies of 60-88% (Villa Sallangos, 2004). Figure 4.3 is a typical Pelton wheel efficiency curve and shows the device efficiency at 80%. Optimally, a Pelton wheel can teach 88% efficiency, but this efficiency must be multiplied by the SWRO pumping device it is connected to in order to produce the overall net transfer efficiency. For example, an 85% efficient Pelton wheel operating with an 82% efficient SWRO pump would have an overall net transfer efficiency of the reject hydraulic flow to the feed water hydraulic flow of approximately 70%. 

The success of Pelton wheels and reverse rutming pumps encouraged pump companies to seek innovations that would improve the economy and applicability of energy recovery technology. The turbocharger was developed as a stand-alone device, not connected to... 

Moderate capital cost compared to Pelton wheel... 

The flow scheme for a typical isobaric energy recovery system is quite different from Pelton wheels or turbochargers and is shown in Figure 4.9. The isobaric energy recovery device is not connected to the high-pressure pump/motor assembly. Additionally, the... 

Higher capital cost (approximately 250% higher than the net capital cost for a Pelton wheel with smaller SWRO pump/motor savings included in calculation)... 

Kuendig, E. (2006a). Pelton wheel energy recovery turbine designed for reverse osmosis applications. In Proceedings AMTA/SCDA Joint Technology Tranter Workshop, Corpus Christi, TX, Feb. 8-9. 

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