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Figure 3 shows how the linearized equations provide an excellent solution with only tiny divergence for big flocs in small tubes.
Figure 4: Floc Spacing vs. Floc Diameter
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insert S eqtn for plate settlers
Figure 5: Minimum spacing vs. Floc Sedimentation
Figure 6: Minimum Plate Settler Spacing vs. Capture Velocity
The Reynold's Number was checked to ensure that the flow in the settler tube is in fact laminar. Next, the entrance region was checked to ensure that the parabolic velocity profile was fully established.
Figure 7: Ratio of Entrance Length to Plate Length vs. Plate Spacing
Figure 7 shows that the entrance regions are always less than the length of the plate setltlers. Thus, based on this analysis, the best designs would include plates that are more closely spaced. All of the plate settlers will have a significant entrance region. It is likely that the only way flocs can successfully pass thorugh the entrance region is to grow into larger flocs so they have a higher sedimentation velocity.