Pressure recovery factor

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. 

For any control valve design be sure to use one of the modem methods, such as that given here, that takes into account such things as control valve pressure recovery factors and gas transition to incompressible flow at critical pressure drop. 

The results of the analysis indicate that the pressure recovery factor is increased by the combination of several oblique shock waves and one weak normal shock wave in order to minimize the entropy increase at the air-intake. 

If the compression stems from one normal shock wave, M4 = 0.45, P04/P01 = 0.213, Pa/Pi = 14.13, and T4/T1 = 3.32. It is evident that the pressure recovery factor obtained by the combination of oblique shock waves is significantly higher than that obtained by one normal shock wave. 

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... 

The pressure recovery factor is a constant for any given valve at a given opening. The value of this factor can be established by flow test and is published by the valve manufacturer. If the actual pressure differential across the valve is greater than the choked pressure differential of Eq. (8-115), then Apcboked should be used in Eq. (8-111) to determine the correct valve size. A more complete presentation of sizing relationships is given in ANSI 75.01.01, including provisions for pipe reducers and Reynolds number effects. 

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. 

C — pressure recovery factor for orifice D inside diameter, ft. ... 

FL liquid control valve pressure recovery factor. 

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