Ring flow

Serizawa et al. (2002) studied the flow patterns in steam-water flow. Figure 2.29 shows their observations in a 0.05 mm glass channel. Here a new pattern was identified, namely, liquid ring flow. 

Further increase in the gas flow rate in liquid ring flow leads to a liquid lump flow, of which the high-speed core gas entrains the liquid phase and liquid lumps slide... 

Figure 5.9 shows various interesting aspects of two-phase flow patterns obtained in this observation. It should be noticed from these pictures that a variety of two-phase flow patterns were encountered in a clean micro-channel. The authors noticed that in a very clean tube, many small individual bubbles flow in a discrete way in the tube without coalescence in bubbly flow. The most interesting thing is the special flow pattern given in Fig. 5.9d, where several bubbles with various shapes are connected in a series by the gas stems located at the tube center line. The liquid ring flow is also clearly seen in Fig. 5.9e. 

Slug-ring flow is the flow in which the probability of B is larger than that of C and the time-averaged void fraction is less than 0.8. 

Figure 4.39 Flow patterns for the nitrogen-water (a) Slug flow Ug — 0.5 m/s, U = 0.1 m/s (b) system observed for the smooth mixer in the annular flow Ug — 5.5 m/s, U = 0.07 m/s (c) microchannel used attheTU/e. The images were ring flow Ug = 20m/s, U = 0.2m/s (d) churn recorded atthe indicated superficial gas (Ug) and flow Ug = 50m/s, U — 0.5 m/s (by courtesy of superficial liquid velocities (U ). The channel has Wiley-VCH Verlag GmbH) [279]. a rectangular cross section of 100 pm X 50 pm.

Feng, 2001 7l=0.003-17.52 m/s, 7g=0.0012- 295.3 m/s. Steam water, ranges not given diameters of 50 pm for air-water, and 25 pm for steam-water two-phase flow, steam- water details not given patterns identified over the ranges of flow rates studied patterns identified liquid ring flow and liquid lump flow. 

Figure 13.31 shows the surfactant composition histories at the effluent end when 1.5% sodium carbonate was added. We can see that all the surfactants with different carbon chains and those with the second carbon chain replaced by the benzene ring flowed out earlier than without the alkali (refer to Figure 13.30). Cio, Cn, and C12 and the ones with their second carbon replaced by benzene ring flowed almost at the same velocity. The flow velocities of C13 and the one with the second carbon replacement changed. This figure shows that the alkali changed the rock surface properties and thus changed the chromatographic separation.

Copper Natural waters Chelex-100 UV-Vis 0.5 pg L"1 Bead injection system with [240] a Jet Ring flow cell ... 

OBubblyflow Slug flow OLiquId ring flow... 

STEP 1 A basic group, B, on the surface of the enzyme removes from the —OH group. STEP 2 Electrons of the H — O sigma bond become the pi electrons of the C=0 bond. STEP 3 A hydride ion is transferred from carbon to NAD" to create a new C—H bond. STEP 4 Electrons within the ring flow to the positively charged nitrogen. 

Arrows 1 and 2 Electrons within the ring flow from nitrogen. 

Compare a thin annular ring flow situation to that for a very thin slit. What do you conclude ... 

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