Expanded flow

Expanded Flow. Expanded dow uses the best aspects of fuimel dow and mass dow by attaching a mass dow hopper section below one that exhibits fuimel dow. The dow pattern expands sufficiendy at the top of the mass dow hopper to prevent a stable rathole from forming in the funnel dow hopper above it. In this way, the dow channel is expanded, material dow is uniform, and the bin height is limited. 

Step 1. Selection of normal operating conditions for the regenerator system. This sets normal air blower flow and head, and expander flow and head. If the proposed installation is being designed for an existing FCC unit, only a... 

Figure 4-109. Effect of adding stages on expander flow capacity and pressure ratio.

As ean be seen from Equation 7-9 and Equation 7-13, it is now possible to ealeulate the redueed expander flow, if the expander pressure ratio is known. To ealeulate pressure ratio, Pj and Pj are needed. In this situation, this ealeulation is for eonditions after the breaker opening. Sinee Pi and P2aft known, it is possible to ealeulate q exp aft- This is elearly illustrated in Eigure 7-7. 

The redueed inlet valve flow, q ean also be ealeulated by eompensating the redueed expander flow, q exp Rom expander inlet eonditions to valve inlet eonditions in other words, from eonditions at point 1 to the eonditions at point 0. It is already assumed that Tq = Tj and Z = Zj and, therefore, it is only neeessary to eompensate for pressure from Pj to P. This ean be formulated as ... 

Jet Rapidly expanding flow exiting from a very small orifice. 

The Bernoulli effect—In a rapidly expanding flow, the two phases accelerate differently. For low initial velocities, the ratio of final velocities at the end of expansion, Va/VL, can be approximated by (pL/pG)u2-... 

When a supersonic flow emerges from a rocket nozzle, several oblique shock waves and expansion waves are formed along the nozzle flow. These waves are formed repeatedly and form a brilliant diamond-Uke array, as shown in Fig. C-5. When an under-expanded flow, i. e., having pressure higher than the ambient pressure is formed at the nozzle exit, an expansion wave is formed to decrease the pressure. This expansion wave is reflected at the interface between the flow stream and the ambient air and a shock wave is formed. This process is repeated several times to form a diamond array, as shown in Fig. C-6 (a). 

For angles greater than 35 to 45°, the losses are normally considered equal to those for a sudden expansion, although in some cases the losses may be greater. Expanding flow through standard pipe reducers should be treated as sudden expansions. 

Watanabe and Niki introduced the coupling of NMR to LC as an on-line detector [20]. After these initial stopped-flow experiments, Bayer et al. [21] reported the first continuous-flow LC-NMR experiment. However, a number of impediments associated with LC-NMR hindered routine analytical application for a number of years. Since then, new instrumentation and analytical methodologies for LC-NMR have been developed and commercialized. The development of high-field-strength magnets, better solvent-suppression techniques, more sensitive small-diameter transmitter/receiver coils, on-column sample preconcentration, and expanded flow cells have improved the sensitivity of LC-NMR. 

For the high-LOX case, where the refrigeration requirement is 186 Btu/lb-mol (434 kJ/kg-mol) of air ow, the required expander ow of 31% is needed to produce less than 3% of the airflow as liquid. This is a simplistic demonstration of the ability of an ASU to produce liquid. For small amounts of LOX, the ASU is efficient. Beyond 3% of the airflow, the distillation impacts of the high expander flow become prohibitive. Above these rates, the addition of compressors/expanders specifically needed for liquefaction are added. 

There is yet another expansion factor we can define, the I/O expansion factor, which we take as the ratio of the outlet flow rate to the inlet flow rate, allowing for the expansion in total flow. From the discussion preceding equation 5.59 we see that the outlet flow rate, allowing for thermal expansion as well as desorption is (Toa/T fo + kmVjT, while the expanded flow of sweeping gas alone at the outlet will be (Toa/Tj,). Hence the I/O expansion feet or is... 

From this we see that the energy balance sets a maximum possible velocity for an expanding flow. Once all the internal energy has been turned into kinetic energy, the gas can no longer accelerate. Obviously, there are other limits to the velocity. Air will turn into a liquid long before it reaches 0°R, and the assumption of constant Cp becomes false at very low temperatures. Furthermore, unless the air were very dry, it would be expected to form a fog at these extremely low temperatures. This explains why high-speed wind tunnels have either big air dryers or big air preheaters. 

Control of fibre orientation with short fibres, such as those sometimes used in injection moulding or reaction injection moulding (RIM) is also important. The flow in the mould may be constrained in two directions such as width and thickness, giving linear flow only in one direction. Or, the flow can instead be radial, that is, constrained in just one direction, for example the thickness, in which case the usual shear forces due to the mould walls will operate, but there will be an additional extensional force, caused by the expanding flow front. This results in fibre orientation being normal to the flow direction. The orientation angle is usually very small at the surface, but it can be almost 90° at the mid-plane [7]. 

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