Useful pumping power

The useful pumping power, P/>, will be less than the power demanded, Pp, because of frictional losses. The pumping power is the power expended in lifting the mass flow, IV (kg/s), to a height // (m) ... 

If the pump manufacturer uses motors for pump power measurement, these motors ate caUbrated to determine the horsepower from the electric power reading and caUbration curves. Such test motors ate recaUbrated periodically, ensuring the same degree of accuracy as shown by the torque meters. 

Development The following discussion relates specifically to the use of what could be called radial-inflow, centrifugal-pump power-recovery turbines. It does not apply to the type of unit nurtured by the hydroelecti ic industry for the 1 ge-horsepower, large-flow, low- to medium-pressure differential area of hydraulic water turbines of the Felton or Francis runner type. There seems to have been little direct transfer of design concepts between these two fields the major manufacturers in the hydroelectric field have thus far made no effort to sell to the process industries, and the physical arrangement of their units, developed from the requirements of the hydroelectric field, is not suitable to most process-plant applications. 

Small probed regions down to 1-2 pm are possible using microscope lenses. Lasers can supply as much pump power as needed to compensate for weaker signals, but a limit is reached when sample heating or nonlinear optically induced processes become significant. 

The power consumed to operate a wet electrostatic precipitator is much less than that required by most other methods of control. There are four areas in which power is consumed (1) electrostatic power, (2) fan power, (3) insulator heating power, and (4) pump power. The total electrostatic power input required for operation is 0.8 to 1.0 kW/1,000 ft of collection area. A comparable piece of equipment is a venturi scrubber with 50-in.wg pressure drop. The power required for this installation would be 6 to 7 kW/1,000 cfm. This would mean that approximately seven times the power would be needed to achieve the same amount of cleaning with a venturi scrubber as opposed to using a precipitator. 

The process flow schematic in Figure 8-6 shows electric motor driven glycol pumps. On smaller systems it is common to use glycol powered pumps. These pumps use the energy contained in the rich (wet) glycol to... 

The power developed on the crankshaft is further depreciated by the requirements of such accessories as the electric alternator, power steering pump, and air conditioner. The drivetrain that connects the crankshaft output to the vehicle drive wheels causes a further loss in power. Drivetrain efficiency generally falls within 80 to 95 percent. The remaining useful propulsive power varies with speed. 

There are some rare situations where the gas turbine is used to power, through direct linkage, a mechanical unit, e.g., a hydraulic fracture pump. 

Copper and copper alloy pipes and tubes are used in large quantities both for conveying fresh and salt waters and in condensers and heat exchangers where fresh or salt waters are used for cooling. Pumps, screens, valves and other ancillary equipment may also be largely constructed of copper alloys. Large tonnages of these materials are therefore used in power stations, on... 

Table 10.6. Composition of various fuels used in power plants. Orimulsion is a very heavy fuel, which is retrieved by pumping steam into the oil-field, thereby giving a mixture of heavy oil and water that is only fluid at elevated temperature.

We measured and analyzed the vertical emission from the resonators under pulsed optical pumping. The experimental setup is illustrated in Fig. 12.8a A Ti/sapphire mode-locked laser was used to optically pump the devices at a center wavelength of 980 nm, repetition rate of 76.6 MHz, and pulse duration of approximately 150 fs. A variable attenuator was used to control the pump power. The average pump power and center wavelength were monitored by a wavemeter, through a 50/50 beamsplitter. The pump beam is focused on the back side of the sample with a 50 x objective lens. A 20 x objective lens is used to collect the vertical emission from the sample and to focus it on an IR camera to obtain the NF intensity pattern and to... 

Figure 17.6 shows five emission spectra obtained from normally identical V = 750 nL EG droplets, with Rh6G concentration of 2 x 10 2 mol L 1. An average pump power of 1.20 mW was used. The observed variation in output power was attributed to fluctuations in the pump power. 

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