Pressure recovery ratio

The same research group also introduced a microfabricated digital wall attachment amplifier [11] for bistable control of flow. An SEM image of a microscale digital wall attachment amplifier formed on PMMA is illustrated in Fig. 6a. The pressure in one of the output ports (opposite to the control port used) is shown in Fig. 6b for various values of the control port pressure. The output pressures were measured at output 2, while the input control pressure was varied at inlet 1. In the experiment, a jet of 330 hPa pressure was supplied through the main nozzle, while the pressures at the control ports were varied from 0 to 12 hPa. The experimental results showed that if the jet was attached to the wall next to a control port, then temporary application of pressure (12 hPa) to that control port guided the jet to the opposite wall. The jet continued to flow along that wall after the removal of the control jet. A minimum supply pressure was needed for the action of this amplifier. The experimental results also showed that the supply pressure had no effect on the pressure recovery (ratio of maximum output to input pressure) and flow recovery (ratio of maximum output to input flow) in this amplifier. 

The resulting overall energy balance for the plant at nominal load conditions is shown in Table 3. The primary combustor operates at 760 kPa (7.5 atm) pressure the equivalence ratio is 0.9 the heat loss is about 3.5%. The channel operates in the subsonic mode, in a peak magnetic field of 6 T. AH critical electrical and gas dynamic operating parameters of the channel are within prescribed constraints the magnetic field and electrical loading are tailored to limit the maximum axial electrical field to 2 kV/m, the transverse current density to 0.9 A/cm , and the Hall parameter to 4. The diffuser pressure recovery factor is 0.6. 

The pressure to be used for reverse osmosis depends on the salinity of the feedwater, the type of membrane, and the desired product purity. It ranges from about 1.5 MPa for low feed concentrations or high flux membranes, through 2.5—4 MPa for brackish waters, and to 6—8.4 MPa for seawater desalination. In desalination of brackish or sea water, typical product water fluxes through spiral-wound membranes are about 600—800 kg/m /d at a recovery ratio RR of 15% and an average salt rejection of 99.5%, where... 

The flow coefficient Cv is determined by calibration with water, and it is not entirely satisfactory for predicting the flow rate of compressible fluids under choked flow conditions. This has to do with the fact that different valves exhibit different pressure recovery characteristics with gases and hence will choke at different pressure ratios, which does not apply to liquids. For this reason, another flow coefficient, Cg, is often used for gases. Cg is determined by calibration with air under critical flow conditions (Fisher Controls, 1977). The corresponding flow equation for gas flow is... 

Measurements of RO Performance. RO performances were measured by the simple apparatus, as shown in Figure 2. The water flux and salt rejection of the hollow fiber membranes under operating pressure in the range of 50 to 120 Kg/cm2c were determined using the feed water of 3.5 NaCl, at 25 C and at product water recovery ratio of less than 1 , after an elapsed time of 2 hrs. 

The RO performance of module was evaluated under operating conditions of pressures in the range of 40 to 75 Kg/cm G, NaCl concentration of feed water in the range of 3-5 to 5.0 and product water recovery ratio of 30 to 60 . 

Figure 9. Applied pressure vs. module performance at various recovery ratio Feed water, 3.5% NaCl solution temperature, 25°C Qp = product water at 55 kg/cm g 30% recovery (-----), cal-...

Module performance and energy consumption were estimated in the case for the desalination of U.2% salinity seawater under high pressure of 75 Kg/cm2c at different recovery ratios. The results are shown in Table 4. 

An internal compression system forms several oblique shock waves and one normal shock wave inside the duct of the air-intake. The first oblique shock wave is formed at the lip of the air-intake and the following oblique shock waves are formed further downstream the normal shock wave renders the flow velocity subsonic, as shown in the case of the supersonic diffuser in Fig. D-1. The pressure recovery factor and the changes in Mach number, pressure ratio, and temperature ratio are the same as in the case of the external compression system. Either external or internal air-intake systems are chosen for use in ramjets and... 

Table 2.67 listed, for the various valve designs, the liquid pressure recovery factors (F,J—which are related to the ratio between the valve pressure drop and the difference between the inlet and the vena contracta pressure—and the cavitation coefficients (Kc)—which are the ratios between the valve pressure drop at which cavitation starts and the difference between the inlet and the vapor pressure—of the application. The allowable maximum Ap before cavitation begins is Ap = Kc (pt - pv). As the FL and Kc values of the different valve designs drop, the probability of cavitation increases. 

Essential oils or ti-limonene are recovered from oil-water emulsions by steam distillation at a reduced temperature. This is not a typical fractional distillation, as practiced when distilling cold-pressed oil, but rather, it is a bulk separation of the volatile compounds in the condensed vapor. When this distillation is applied to pure ti-limonene, the mass ratio of water d-limonene at atmospheric pressure is in the range of 8-10 1. In the actual oil emulsions, considerably more water must be distilled to recover a given quantity of rf-limonene, because this component is adsorbed by the pulp particles in the emulsion. If the distillation is performed in a continuous manner under pressure, the ratio of water removed per amount of (i-limoncne recovered can be reduced to 3 4 1 (Braddock, 1999). However, when the steam temperature rises above 120°C, recovery of d-limonene decreases due to formation of some water-soluble alcohols and epoxides, which are soluble in the aqueous phase and are not recovered in the d-limonene phase above the condensate. 

Spiral -100 to 400°C <1.8 MPa use with sludges, slurries, high-viscosity materials (especially 4 X 10" to 4 X 10 mPa s) >90% heat recovery. High heat transfer coefficients low pressure drop. Ratio of flow rates being handled <3.5. Not when AFj AT2. Area 4 to 100 mT... 

In RO, the osmotic pressure of a solution has to be overcome by an applied transmembrane pressure to achieve solvent flux and separation. Recovery (ratio of product/feed) has a high impact on flux and rejection, and both decrease with increasing recovery. 

Percentage free area offered for the fiow (the ratio of the free area available for the fiow, i.e. total cross-sectional area of holes on the orifice plate to the total cross-sectional area of the pipe). Lower free areas must be used for producing high intensities as the rate and magnitude of pressure recovery affects the dynamics and the collapse of the cavities and hence the desired beneficial effects. 

Feed pressure Feed water temperature 6.0 bar 25.0°C (77°F) Permeate recovery ratio 75.0%... 

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