Gas-liquid hydrodynamics in Taylor Flows with complex liquids Chapter V - 108 -
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5. Conclusions
With the HSV the flow’s condition and the bubble’s velocity have been found and it was fundamental in order to obtain the results with the PIV. That made possible the graphics with PIV. Besides it was possible to verify that the calibration, made with the PIV as well, gave acceptable values of the particles’ velocity and that it turned out to be comparable with the one obtained previously for the fluid. Using the bubble’s velocity from PIV, the error from the real value would be high and therefore the results would be wrong. Substantially the liquids used are water, water and ludox and glycerol 50% per weight solution: the velocity of bubble is evaluated, given that each second the camera does 250 frames, and the meter has been put behind the capillary The liquid’s velocity is evaluated with the volume’s flow of the liquid, then this flow is divided to the surface area of the section of the capillary. The glycerol is used to increase the viscosity of the fluid. This increase improves the relaxation time that permits a slow sedimentation of alumina particles inside the tank and the behavior is Newtonian. To confirm the information reported on the label of the product O some test have been effettuated in order to verify the real size of the alumina's particles . From the obtained data with bigger particles the percentage per volume major of the particles has size as expected from the label. From the obtained data with smaller particles the percentage per volume major of the particles hasn't size as expected from the label. This difference is developed from the agglomeration of the particles. The experiments done have
confirmed the theory of relaxation time. In particular the alumina particles’ motion does not
Gas-liquid hydrodynamics in Taylor Flows with complex liquids
structured slurry bubble column. flow is:
given that the different density are considered: in fact during this work the complex liquids have been used.
In particular :
• If τ < 10-3: 10-8 , the particles follow the liquid’s flow • If τ > 1, the particles don’t follow the liquid’s flow
The results of velocity give different profiles of velocity: for water and water and ludox solution the profile is similar to plug flow, whereas for the glycerol with alumina the profile is like plug flow but with some noise. The alumina particles were used because they
inside the structured slurry bubble column. In the first two instances the rate of strain and the vorticity are symmetrical in the channel, whereas in the alumina and glycerol solution
symmetry. The flow which is inside
chaotic. It seems that there aren't vortex because there isn't a several point where the vortex are born ; this has implications models used to predict rates of mass transfer and chemical re
monolith reactors.
liquid hydrodynamics in Taylor Flows with complex liquids Chapter V
structured slurry bubble column. In this study τ used to classify the different behaviours of the
given that the different density are considered: in fact during this work the complex liquids have
, the particles follow the liquid’s flow > 1, the particles don’t follow the liquid’s flow
velocity give different profiles of velocity: for water and water and ludox solution the profile is similar to plug flow, whereas for the glycerol with alumina the profile is like plug flow but with some noise. The alumina particles were used because they can round the catalyst structured slurry bubble column. In the first two instances the rate of strain and the vorticity are symmetrical in the channel, whereas in the alumina and glycerol solution
The flow which is inside the capillary and where there are the alumina particles is more chaotic. It seems that there aren't vortex because there isn't a several point where the vortex are
this has implications models used to predict rates of mass transfer and chemical re liquid hydrodynamics in Taylor Flows with complex liquids
- 109 - erent behaviours of the
given that the different density are considered: in fact during this work the complex liquids have
velocity give different profiles of velocity: for water and water and ludox solution the profile is similar to plug flow, whereas for the glycerol with alumina the profile is like plug can round the catalyst structured slurry bubble column. In the first two instances the rate of strain and the vorticity are symmetrical in the channel, whereas in the alumina and glycerol solution there is no the capillary and where there are the alumina particles is more chaotic. It seems that there aren't vortex because there isn't a several point where the vortex are this has implications models used to predict rates of mass transfer and chemical reaction in
