Inlet configurations axial

End-suction and multi-stage pumps with in-line impellers are prone to excessive axial thrusting. In the end-suction pump, the centerline axial inlet configuration is the primary source of thrust. Restrictions in the suction piping, or low suction pressures, create a strong imbalance that forces the rotating element toward the inlet. 

Premix duct based on a lean premixed prevaporised (LPP) concept with a venturi configuration, which has been optimized in order to obtain a good velocity profile at the inlet to the catalytic section. Fuel is injected upstream of the venturi minimum section with injectors angled relative to the airflow. Mixing is achieved with an inlet radial/axial turbulence generator in the venturi inlet. 

Fig. 1.3.8. Side and top views of the four most used inlet configurations, a circular or pipe inlet, b slot (also called tangential ) inlet, c wrap-around inlet, and d axial inlet with swirl vanes...

The axial flow compressors in aero gas turbines are heavily loaded. The aspecl ratio of the blades, especially the first few stages, can be as high as 4.0, and the effecl of streamhne curvature is substantial. The streamline configuration is a function of the annular passage area, the camber and thickness distribution of the blade, and the flow angles at the inlet and outlet of the blades. The shafts on these units are supported on antifriction bearings (roller or ball bearings). 

Figure 6.6 uses a particular problem to illustrate some of the salient differences between the semi-infinite and finite-gap configurations. In both cases the net flow rates are the same, and the streamlines in both plots have the same values. The streamlines for the finite-gap problem show pure axial flow at the inlet, whereas the semi-infinite case shows radial spreading everywhere. The radial-velocity profiles are quite different, with the finite-gap profile showing no slip at both boundaries. 

Fig. 6.6 Comparison of two alternative stagnation-flow configurations. The upper illustration shows the streamlines that result from a semi-infinite potential flow and the lower illustration shows streamlines that result from a uniform inlet velocity issuing through a manifold that is parallel to the stagnation plane. Both cases are for isothermal air flow at atmospheric pressure and T = 300 K. In both cases the axial inlet velocity is u = —5 cm/s. The separation between the manifold and the substrate is 3 cm. For the outer-potential-flow case, the streamlines are plotted over the same domain, but the flow itself varies in the entire half plane above the stagnation surface. The stagnation plane is illustrated as a 10 cm radius, but the solutions are for an infinite radius.

Another configuration for hydrodynamic focusing is to create a non-axial sheath flow, as shown in Figure 8.39. The sheath inlet resembles the one used in usual microchip focusing experiments. The non-axial sheath flows are supplied... 

Boundaries in fast fluidization refer mainly to the column wall as well as the inlet and outlet. Effect of the wall on pressure drop due to friction between the fluidized solids and the wall surface is minimal (Li et al, 1978), although it is the very cause of radial distribution of parameters. The configuration of the inlet and the outlet often strongly affect gas-solids flow, especially with regard to axial voidage profile. 

The results of Fig. 13.6 were compared with a 1D axial dispersion model of the same process configuration (i.e., two injector loops, two lines from the loops to the mixing tee, the reactor tubing, and the sample loop tubing with the dimensions cited earlier). The output for the case of a 10 pL min flow rate from each pump, with 10 wt% Tracer 1 injected simultaneously from each injection loop, is shown in Fig. 13.7. The model predicted analytical loop peak concentration (i.e., exceeding 99% of the inlet injector concentration) arrived earlier than the peak concentration resulting from the actual process data. 

Figure 10-2. Reverse vortex flow system for gliding arc discharge stabilization (a) eonflgu-ration with a movable ring electrode (b) configuration with a spiral electrode. In the figures, (1) quartz tube (2) cylindrical reactor volume (3) swirl generator with tangential inlet holes (4) additional axial gas flow inlet (5) gas flow exit ...

This configuration is also sometimes called a tangential inlet, but we reserve this term to distinguish from axial inlets with swirl vanes... 

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