Pumps power requirements for

For extreme intensities, lasers can only be operated in pulsed rather than CW fashion, due to the heating of the cavity and the high pumping power required for the population inversion. Laser pulses with peak powers of 2.5 x 1013 watts have been achieved of course, such a pulse lasts for only a rather short time (10-12 sec). 

The pumping power requirement for a laminar flow piping system can be reduced by a factor of 16 by doubling (he tube diameter. 

C How is lire friction factor for flow in a lube related to the pres.sure drop How is the pressure drop related to the pumping power requirement for a given mass flow rate ... 

Eigure 20 shows a comparison of performance of the narrow channels with that of the sprays and microjets. The pumping power required for the narrow chaimels lies between those for the sprays and the... 

Determine the pump power required for this pipeline. How will the power requirement change if the flow rate is increased by 20% ... 

Using Bowen s method, develop a general scale-up procedure for predicting the pressure gradients in turbulent flow of this rock slurry. Estimate the pump power required for a flow rate of 0.45 m /s in a 400 mm diameter pipe, 500 m long. The pump has an efficiency of 60%. Take the density of slurry 1250 kg/m. ... 

At Fukushima Daiichi Unit 1, an anticipated 920 MW of energy would be transferred to the sea every hour while the plant was operating at full-power (given fliat it would produce 460 MW of electric power, at a level of one third efficiency (Van Wylen and Sonntag, 1973), twice the energy would be rejected versus the electricity produced). If we assume that a 90 °F sea water temperature is the maximum that can be allowed for marines life safety, it is easy to calculate the minimum pumping power required for this process. It turns out that at full power operation, the Fukushima Daiichi sea water pumps would need to move about 220,000 gal/min to sufficiently cool the turbine exhaust steam. 

A homogenize is a high pressure positive pump with three, five, or seven pistons, that is driven by a motor and equipped with an adjustable homogenizing valve. Smoother flow and greater capacity are obtained with more pistons, which force the product iato a chamber that feeds the valve. In design and operation, it is desirable to minimize the power requirements for obtaining an acceptable level of homogenization. At 17.2 MPa (2500 psi) and a volume of 0.91 t/h (2000 lb/h), a 56-kW (75-hp) motor is required. 

Power requirements for spiral plants are low, consisting primarily of pumping energy and possibly a thickener or other pulp-handling equipment associated with the flowsheet. 

Appendix Rules of ihumb for every day use 12/323 Power requirements for pumps 12/323 Power requirements for lifts 12/323 Power requirements for fans 12/323... 

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 charts showing the p>erformance of duplex pumps are shown in Table 4-38 [17]. The charts showing the performance of triplex pumps are shown in Table 4-39 [17]. A chart listing the pump output required for a given annular velocity is shown in Table 4-40 [18]. A chart listing the power input horsepower required for a given pump working pressure is shown in Table 4-41 [19]. 

The power required for pumping will be given by the product of the volumetric flowrate and the pressure difference between the pump outlet and the discharge end of the pipeline. Taking note of the fluctuating nature of the flow, it is necessary to consider the energy transferred to the fluid over a small time interval and to integrate over the cycle to obtain the mean value of the power. 

The power requirements for the pump may now be calculated front equation 8.71. 

Power requirements for compressors and vacuum pumps must be considered when wiring plans are made. Both compressed air and vacuum are frequently used in laboratories. Sometimes both can be piped to more than one laboratory room from a central location. Air pressure will usually be sufficient for laboratory applications, but vacuum may not always be, in which case a separate vacuum pump would be required. 

The power required for pumping an incompressible fluid is given by ... 

Operating costs for injection wells are significantly lower when compared to capital costs. They include labour for operation and maintenance, chemicals for pretreatment, and power for pump operation (Mickley 2006). During operation of the well, the power required for pumping is the most significant cost (Mickley 2006). 

Along with electronic transport improvements must come attention to substrate transport in such porous structures. As discussed above, introduction of gas-phase diffusion or liquid-phase convection of reactants is a feasible approach to enabling high-current-density operation in electrodes of thicknesses exceeding 100 jxm. Such a solution is application specific, in the sense that neither gas-phase reactants nor convection can be introduced in a subclass of applications, such as devices implanted in human, animal, or plant tissue. In the context of physiologically implanted devices, the choice becomes either milliwatt to watt scale devices implanted in a blood vessel, where velocities of up to 10 cm/s can be present, or microwatt-scale devices implanted in tissue. Ex vivo applications are more flexible, partially because gas-phase oxygen from ambient air will almost always be utilized on the cathode side, but also because pumps can be used to provide convective flow of any substrate. However, power requirements for pump operation must be minimized to prevent substantial lowering of net power output. 

COMMENTS The Carnot vapor cycle as illustrated by Example 2.1 is not practical. Difficulties arise in the isentropic processes of the cycle. One difficulty is that the isentropic turbine will have to handle steam of low quality. The impingement of liquid droplets on the turbine blade causes erosion and wear. Another difficulty is the isentropic compression of a liquid-vapor mixture. The two-phase mixture of the steam causes serious cavitation problems during the compression process. Also, since the specific volume of the saturated mixture is high, the pump power required is also very high. Thus, the Carnot vapor cycle is not a realistic model for vapor power cycles. 

A Carnot engine with a steady flow rate of 1 kg/sec uses water as the working fluid. Water changes phase from saturated liquid to saturated vapor as heat is added from a heat source at 300° C. Heat rejection takes place at a pressure of lOkPa. Determine (1) the quality at the exit of the turbine, (2) the quality at the inlet of the pump, (3) the heat transfer added in the boiler, (4) the power required for the pump, (5) the power produced by the turbine, (6) the heat transfer rejected in the condenser, and (7) the cycle efficiency. 

The power-generating potential of a water-dominated resource depends on the geothermal fluid temperature and production flow rate (Fig. 2). The figure gives the net power output, which accounts for parasitic loads caused by the condenser and feed pump power requirements. The output power from two-phase water-steam or steam alone is much greater than the curves shown for liquid in Fig. 2. 

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