Plugs length

Weber (1973) has put forth a rather simple approach to pulsed piston modeling which couples the gas and solid behavior. The expression that Weber suggested is given in Eq. (9). One notes that this expression has an exponential decay of the pressure as the plug length decreases. This behavior has often been seen in industrial operations. 

Figure 21. Pressure drop versus plug length. (Aziz and Klinzing, 1990.)...

Linear plot including plug length Nonlinear regression... 

The data clearly can be only approximately correlated in terms of the open area fraction as shown in Fig. 27. Subsequently we studied the effect of the plug length on the inertial losses coefficient for a clean filter at the three different... 

Fig. 28. Contraction/expansion losses coefficient vs. open area fraction for different cell densities and plug lengths.

Equation 26-16 multiplies the plug length times its cross-sectional area to find its volume and then multiplies by concentration to find the moles in that volume. 

A mixture of 1 mmol of the corresponding 4-hydroxy-2( 1 //)-pyridonc 1 and 4.5 mmol of benzyl-, 1-phenylethyl- or 2-phenylethylamine 2 was filled into a 15-mL pressure tube (Aldrich, with threated type A plug, length 10.2 cm and additionally provided with a Teflon ring). Then the reaction tube was placed in the center of an 800-mL beaker which was filled with vermiculite, a polymeric material for covering hazardous compounds in packages. After irradiation in an ordi-... 

Figure B. 1 shows the layout of the one-sided form in CSMPlug by selecting the 1 SD tab. Inputs to the model are upstream and downstream temperature and pressure, equilibrium pressure, hydrate structure, plug porosity, permeability, diameter of the pipeline, and plug length. Input details are given by placing the mouse at each input box.

M 77] [P 67] When mixing plugs, it is desired to have fast mixing similar to steady flows however, in addition, the axial dispersion should be minimized, since the corresponding increase in plug length should be kept minimal [156],... 

If reduction in the calculated plate number Nr is considered as criterion for the tolerable injection plug length and if Nr is given by... 

A reduction parameter 8 of 0.091 corresponds to a 10 % increase in peak variance. The dependence of the peak width on the injected plug length for alkyl and aryl benzoates in packed CEC was investigated experimentally [30]. At low injection plug... 

Sample volume overloading can also reduce efficiency—for example, when the sample plug length is wider than the zone length determined by diffusion. This liability of high injectable volumes is often ignored, and efficiency is intentionally sacrificed to gain sensitivity. 

Several different methods to distribute the liquid have been tested. Flooding the monolith with liquid for a short time gives distribution to all channels. However, the linear velocity in the monolith is very high, 0.2-0.5 m/sec. An optimal plug length of gas and liquid is 1-2 cm, giving a pulsing frequency of 10-50 Hz. Furthermore, this method does not provide an even liquid distribution unless the liquid is added very fast or very uniformly over the monolith. 

Size Body Volume (ml) Internal Volume (ml) Maximum Plug Length (mm) Maximum Plug Volume (ml)... 

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