Nozzle exit

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. 

From the velocity diagram in Fig. 29-13 it is apparent that an increase in wheel peripheral velocity [L permits an increase in nozzle exit velocity C] without increasing Co- Accordingly, a high-speed tur-... 

The minimum liquid head above the drawoff nozzle must be greater than the nozzle exit resistance. Based on a safety factor of 4 and a velocity head K factor of 0.5 ... 

Nozzle Diameter, d Nozzle exit diameter will be equal to or less than the diameter of the line feeding the tank. For a known flow rate of fluid supplied to the jet, the diameter is set by the largest size that will satisfy the requirement that the jet be turbulent or will satisfy the nozzle discharge velocity requirement (if the jet is denser than the tank liquid). For a turbulent flow requirement (both heavy and light jets) ... 

Insert with channels to provide high velocity swirl motion at nozzle exit... 

Nozzle exit velocity Dispersion media and rate... 

F = (H+ cosor) (wVe/g) + (Pe-P0)Ae where oc = half of the divergence angle of the nozzle, w - weight rate of proplnt flow, g = acceleration of gravity, Ve = exit flow velocity, Pe = nozzle exit pressure, PQ = external atm pressure, and Ae = cross section at nozzle exit plane. An effective exhaust velocity is defined by... 

A sample PIV image and the corresponding two-dimensional velocity map. The axial velocity along with distance from nozzle exit is plotted accordingly. This minimum point is defined as the reference flame speed. At this reference point, the linearity of the radial velocity profile is illustrated. 

The experimental setup sketched in Figure 5.2.3 comprises a burner with ad = 22 mm nozzle exit diameter and a driver unit (loudspeaker) fixed at its base. The burner body is a cylindrical tube of 65 mm inner diameter containing a set of grids and a honeycomb followed by a convergent nozzle with an area contraction ratio of cr= 9 1. 

This system produces a steady laminar flow with a flat velocity profile at the burner exit for mean flow velocities up to 5m/s. Velocity fluctuations at the burner outlet are reduced to low levels as v /v< 0.01 on the central axis for free jet injection conditions. The burner is fed with a mixture of methane and air. Experiments-described in what follows are carried out at fixed equivalence ratios. Flow perturbations are produced by the loudspeaker driven by an amplifier, which is fed by a sinusoidal signal s)mthesizer. Velocity perturbations measured by laser doppler velocimetry (LDV) on the burner symmetry axis above the nozzle exit plane are also purely sinusoidal and their spectral... 

In this equation Uq is the nozzle exit velocity and d is the nozzle diameter. 

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... 

The rocket scientists wanted to be able to predict the thrust that could be expected from a fuel of a certain composition (see historical sketches by Zeleznik and Gordon, 1968 van Zeggeren and Storey, 1970 Smith and Missen, 1982). The volume of gases exiting the nozzle of the rocket motor could be used to calculate the expected thrust. The scientists recognized that by knowing the fuel s composition, the temperature at which it burned, and the pressure at the nozzle exit, they had uniquely defined the fuel s equilibrium volume, which they set about calculating. 

In internal mixing atomization (for example centrifugal-pneumatic atomization), 159] the liquid metal and gas enter the swirl jet atomizer tangentially under pressure (Fig. 2.13)J159] The two fluids rotate, form a mixture, and accelerate in the confuser. Due to the strong centrifugal force, the liquid metal forms a film at the nozzle exit even without the presence of the gas. With the applied gas, the liquid film is atomized into a fine dispersion of droplets outside the nozzle. 

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