Advanced Imaging & Measurement for Multiphase Flows
Case 2. Periodical flows
Extends of EIT to the periodical oscillated two-phase flow in an oscillatory baffled reactor (OBR) were challenged (Figure 4). This is enabled through deployment of the third generation of ERT systems operating at ultra-fast speed (exceeding 1000 frames per second) and periodical sampling. Periodical concentration distributions caused by strokes of the OBR piston have been visualized using a 3D interpolation method (Figure 5), which revealed the effect of the oscillatory frequency being a larger impact on the mixing performance compared to the oscillatory amplitude. It was known that the conventional cross-correlation method is not able to extract dynamics of periodical flows. With a periodical sampling method developed in the study, pulsation velocity profiles were successfully extracted (Figure 6).
|Figure 4: An oscillatory baffled reactor fitted with EIT sensors .|
Figure 5: Concentration distribution in OBR .
Figure 6: Extracted oil flow velocity profiles in OBR with different sampling lengths
Author Information: Mi Wang, Institute of Particle Science and Engineering, School of Process, Environmental and Materials Engineering, Email: firstname.lastname@example.org
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