Dependence on liquid flow rate

When straight or serrated segmental weirs are used in a column of circiilar cross secdion, a correction may be needed for the distorted pattern of flow at the ends of the weirs, depending on liquid flow rate. The correction factor F from Fig. 14-33 is used direcdly in Eq. (14-112) or Eq. (14-119). Even when circular downcomers are utilized, they are often fed by the overflow from a segmental weir. When the weir crest over a straight segmental weir is less than 6 mm V in), it is desirable to use a serrated (notched) weir to provide good liquid distribution. Inasmuch as fabrication standards permit the tray to be 3 mm Vh in) out of level, weir crests less than 6 mm V in) can result in maldistribution of hquid flow. 

Study of onset of flooding in tubes 8-15.8 mm. diameter, 1200 mm. long with downward water films, counter-current air stream of 0.5-12 m. sec. Gas velocity to cause flooding found to depend on liquid flow rate and tube diameter. 

Absorption of hypochlorous acid into water, a liquid-side mass transfer-limited process, showed HTU values as low as 4 cm, with a strong dependence on liquid-flow rate. Heat of absorption removal was identified as a potential issue with absorption in rotating beds (9). 

Figure 5. Summary of measurements on the dependence on liquid flow rate.

Figure 4.10 Simulated conversions and catalyst wetting depending on liquid flow rate.

Figure 5.1 Pesticides included in the systematic investigations on APCI-MS signal response dependence on eluent flow rate the parameter IsTow represents the distribution coefficient of the pesticide between n-octanol and water. Reprinted from J. Chromatogr, A, 937, Asperger, A., Efer, 1., Koal, T. and Engewald, W., On the signal response of various pesticides in electrospray and atmospheric pressure chemical ionization depending on the flow rate of eluent applied in liquid chromatography-mass spectrometry , 65-72, Copyright (2001), with permission from Elsevier Science.

Tubular Reactors In a tubular or pipeline reactor, gas and liquid flow concurrently A variety of flow patterns, ranging from a small quantity of bubbles in the liquid to small quantities of droplets in the gas, are possible, depending on the flow rate of the two streams. Figure 19-26/ shows the patterns in horizontal flow those in vertical flow are a little different. 

In the present research, we study two fundamental properties of bubble columns liquid hold-up and mixing. Both of these properties depend on the flow rates of the gas and liquid phases. These two properties may be considered response variables in the sense that their values depend on the way bubbles are formed. We present results for two types of bubble generating devices (or, for short, spargers) i.e. perforated rigid plates and perforated rubber sheets. An advantage of the rubber-sheet sparger is the self-cleaning feature. This is... 

That the cross-section of a jet of liquid from a non-circular orifice vibrates between the form of the orifice and a circle was first observed by Bidone.i This produces a series of waves. The explanation of the phenomenon as due to surface tension was given by BufF, the mathematical theory and experimental method being developed by Lord Rayleigh. Piccard and Meyer used the method for comparative measurements, refinements being introduced by Pedersen and Bohr. Rayleigh showed that for an ideal jet of radius r at its circular section, the time of oscillation is r=Ki(Qr layi where q is the density of the liquid. For an actual liquid r depends on the flow-rate and corrections are necessary. The period r is related to the directing force F and moment of inertia I by the equation t=7t(IIF) f. Since I is proportional to the mass or density and depends in an unknown way on the form of the orifice, and F is proportional to the surface tension a, it follows that r=7iA(Qla) where is a constant. Since r=l jn and where A=wave-... 

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