Nozzle exit area

The mass velocity G = w/A, where w is the mass flow rate and A is the nozzle exit area, at the nozzle exit is given by... 

Equation (6-128) does not require fric tionless (isentropic) flow. The sonic mass flux through the throat is given by Eq. (6-122). With A set equal to the nozzle exit area, the exit Mach number, pressure, and temperature may be calculated. Only if the exit pressure equals the ambient discharge pressure is the ultimate expansion velocity reached in the nozzle. Expansion will be incomplete if the exit pressure exceeds the ambient discharge pressure shocks will occur outside the nozzle. If the calculated exit pressure is less than the ambient discharge pressure, the nozzle is overexpanded and compression shocks within the expanding portion will result. 

Bedload was sampled during competent flows at the same vertical than suspended sediment. Bedload analysis has been based upon 215 samples, 145 during 2002-2003 and 70 during 2003-2004. At SMS we used a 29-kg cable-suspended Helley-Smith sampler with a 76-mm intake and an expansion ratio (i.e. ratio of nozzle exit area to entrance area) of 3.22 (Fig. 2c). Bedload was measured at... 

Ve = velocity of gases at nozzle exit Ae = nozzle exit area Pe = nozzle exit pressure P, = surrounding atmospheric pressure. 

For a fixed vehicle diameter and thus a fixed maximum nozzle exit area, higher area ratios are obtained at higher pressures simply because the throat area decreases for fixed mass flow. This is the major effect of pressure and, indeed. contributes to increase the performance for both atmospheric and space operation. 

Aj is the fully expanded jet area, 7 is the jet total temperature. Vj is the fully expanded jet velocity, RHOj is the fully expanded jet density. Ag is the nozzle exit area, Mj is the fully expanded jet Mach number, Mnozzle design Mach number, 7 is the ratio of specific heats at the nozzle exit. V) is the initial and final aircraft velocity, AOA is the aircraft angle of attack, and Altitude is aircraft height above ground. 

Figure 16.2 shows the spatial arrangement of round and slot nozzles in arrays and the averaging area appropriate to each. Let /is the nozzle exit area/area of square or hexagon attached to it. The following table defines /for the triangular or square pitch round nozzles and parallel slot arrays ... 

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