Characteristic curves for

Generalized Correlations. Generalized correlations are often the only recourse when a property value cannot be determined from empirical correlations or by other means. Several powerful correlating techniques fall under this category, including the principle of corresponding states (3,17), reduced property models (1), and the Polanyi-type characteristic curve for microporous adsorbents (14). 

For a given set of assumptions it is possible to calculate the characteristic curves for the product from the ciystaUizer when it is operated at various levels of fines removal as characterized by Lj. This has been done for an ammonium sulfate crystalhzer in Fig. 18-63. Also shown in that figure is the actual size distribution obtained. In calculating theoretic size distributions in accordance with the Eq. (18-41), it is... 

FIG. 22-65 Characteristic curve for flux as a function of pressure for cross-flow membrane processes limited by mass transfer at the membrane. 

To make a proper selection of HRC fuses it is essential that the current-time characteristic curves for Ihe releases of the breaker and the fuses are available from their manufacturers. 

The control-to-output characteristic curves for a current-mode controlled flyback-mode converter, even though it is operating in variable frequency, are of a single-pole nature. So a single pole-zero method of compensation should be used. The placement of the filter pole, ESR zero, and dc gain are... 

Figure 9.42 shows the typical characteristic curve of a centrifugal fan, where the blades are backward curved. The figure also shows the theoretical characteristic curve when the slip factor is 1 and when it is smaller than 1. Characteristic curves for a real fan are closer to the isentropic one at the design point. At this point the efficiency is maximum. 

Consider the fan characteristic curves for two different rotational velocities ft] and n-,. Select the operating point for the characteristic curve as The corresponding point is q,i) for characteristic curve n. ... 

FIGURE 9.53 Fan characteristic curve for two rotational velocities, n, and rij, and three fan affinity parabolas. 

The speed of an electric motor can be changed by altering the frequency of the electric current. This is because the ratio is the same as 60 or 50 f/p (f = the frequency of the current, p = the number of poles in the stator). Frequency converters are built of electronic components, frequently combined with microprocessors. They provide good motor protection and are superior to the traditional bimetal protection. The characteristic curve for a pump and fan motor is also quadratic, making lower demands to the frequency converters When the frequency of the electrical current is changed in the frequency converter, the main AC supply is transformed into DC. The DC is then treated... 

It is important to recognize that a cenlrijugal pump will operate only along its performance curve [10, II]. External conditions will adjust themselves, or must be adjusted in order to obtain stable operation. Each pump operates within a system, and the conditions can be anticipated if each component part is properly examined. The system consists of the friction losses of the suction and the discharge piping plus the total static head from suction to final discharge point. Figure 3-51 represents a typical system head curve superimposed on the characteristic curve for a 10 by 8-inch pump with a 12-inch diameter impeller. 

Figure 12-26. Horsepower characteristic curves for constant discharge pressure, k = 1.3. (Used by permission Cooper-Cameron Corporation.)...

Figure 12-130A. Characteristic curves for straight radial blade. (Used by permission The Howden Fan Company.)...

Figure 4-316 shows the characteristic curves for a new 8-in. OD, 7 8 lobe, and three stages. 

Most pump manufacturers provide composite curves, such as those shown in Fig. 8-3, that show the operating range of various pumps. For each pump that provides the required flow rate and head, the individual pump characteristics (such as those shown in Fig. 8-2 and Appendix H) are then consulted. The intersection of the system curve with the pump characteristic curve for a given impeller determines the pump operating point. The impeller diameter is selected that will produce the required head (or greater at the specified flow rate). This is repeated for all possible pump, impeller, and speed combinations to determine the combination that results in the highest efficiency (i.e., least power requirement). Note that if the operating point (Hp, Q) does not fall exactly on one of the (impeller) curves, then the... 

Draw the Ah against Q characteristic curves for each pump together with the system Ahs against Qs curve on the same plot as shown in Figure 4.9. 

Figure 5. Characteristic curve for sensitivity measurement on the 65/35 copolymer.

FIGURE 3.25 Graphs of hydraulic conductivity vs. volumetric water content showing characteristic curves for different sediments from the VOC-arid site integrated demonstration at the Hanford site. 

FIG. 24-59 Characteristic curves for boiler thermal efficiency as a function of flue gas effluent temperature and flue gas water dew points. Based on the LHV of a fuel, and stoichiometric reaction, 100 percent efficiency would be achieved if sufficient combustion heat were recovered and removed, so that the temperature of the effluent flue gas was reduced to 25°C. For a flue gas with a 55°C dew point, recovering additional heat via condensation by cooling from 175 to 35°C (as shown) would increase the overall efficiency by more than 13 percent. Courtesy Combustion b- Energy Systems, Ltd. www.condexenergy.com.)... 

Horizontal centrifugal pumps should provide 150% of the rated capacity at 65% of the rated pressure, with a shutoff head of not more than 120% of the rated pressure. This pump should be used only when suction supply is under a positive head. Suction pipes should be designed to preclude the formation of air bubbles. A characteristic curve for a rated fire water pump is shown in Figure 7-15. 

In general, we can run the temperature sweep as either a Parametric Sweep or a Secondary Sweep. However, to generate I-V characteristic curves for different temperatures, we must use the Secondary Sweep. Click on the square D next to the Secondary Sweep selection ... 

The nested DC Sweep can be used to generate characteristic curves for transistors. We will illustrate generating these curves using a BJT. Wire the circuit below ... 

The current/voltage characteristic curves for the reduction of 2 on chelate catalysts mostly show a Tafel region with a slope of about 60 mV. This could... 

Figure 15.4. Polanyi characteristic curve for effect of temperature on adsorption of n-butane on silica gel [Al-Sahhat et al., Ind. Eng. Chem. Process. Des. Dev. 20, 658 (1981)].

Figure 18.7 Characteristic curve for a proportional counter. (From Wang et al., 1975.)...

Figure 3.6 Screw and die characteristic curves for a 45 mm diameter extruder with an PE-LD.

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