Bubbling, time sequence

Figure 2.64 Time sequence showing the movement and coalescence of an ensemble of bubbles in a narrow capillary, taken from [185].

FIGURE 1.8 Time sequence illustrating one period of the cycle of bubble production from the lumen of a typical hollow cellulose fiber adsorbed on the wall of a glass poured with champagne from Frame 1 to Frame 5, the time interval between successive frames is about 200 ms, but from Frame 5 to Frame 6, the time interval is only 1 ms (bar = 50 pm) (Photographs by Cedric Voisin and Gerard Liger-Belair). 

A representative time sequence of four PIV/LIF-derived velocity vector distributions together with the SIT-derived bubble shadows is plotted in Figure 16 as a typical result obtained by the PIV/LIF/SIT system. Note that even with LIF technique used, there are also "white-out" regions (intensity saturation), and the laser sheet entering from the... 

A time sequence of bubbling from such a calculation of the IGT six-inch EGO-33 run is shown in Figure 3. The sequence is that of a stationary or quasi-steady pattern of bubble evolution subsequent to the start-up transient. In each individual "frame" of the time sequence a reactor section, bounded by the centerline axis on the left and the reactor radius on the right, is shown. The representative particles are indicated by the black dots while the bubbles and the voids are white. The time corresponding to discrete frames is indicated on the base of the figure and the rise of the bubbles, together with the solids mixing, can be discerned in that sequence of frames. This... 

Figure 3. Time sequence of bubble evolution during steam oxygen gasification in IGT 6-in. diameter bench scale reactor...

FIGURE 3-24 Left Four plane capacitance sensor with driven guard electrodes located near the distributor in fluidized bed (distances in mm) Adapted from Beck et. al. (1995) Right Bubbles (dark) attached to a wall of bed in time sequence (see also Wang et. al. 1996)... 

There are 15 operatiOTi modes for the capillary system with a 1 x 4 microfluidic switch, which could simultaneously switch the liquid into the desired outlet ports, as listed in Table 1. The operation modes could be divided into two parts, namely, single and multiple-output modes. We will discuss the required time-sequence power control for the bubble nucleation... 

Applying the similar principles, we could cmitrol the fluid into multiple microchannels based on the needs. For such multiple-output modes, there are three different operation methods, as shown in Fig. 9, to control the fluid into the microchannels 2 and 4, for example, in the capillary system with a 1 X 4 microfluidic switch. The time-sequence actuation as shown in Fig. 9a, we would generate the growth and collapse of the thermal bubble six times to cmitrol the fluid to pass through the microchannels 4 and 2. The bubble pressure overcomes the barrier pressure to make the fluid pass through all hydrophobic patches of microchannels 2 and 4. Then, the capillary force pulls the fluid through to turn on microchannels 2 and 4. However, Fig. 9b demonstrates the same switch functimi with only... 

Bubble-Actuated Microfluidic Switch, Fig. 9 The three different time-sequence power control logics to turn on... 

Cheng CM, Liu CH (2006) A capillary system with thermal-bubble-actuated IxN micro fluidic switches via time-sequence power control for continuous liquid handling. J MEMS 15(2) 296-307... 

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