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#1)Wall Friction: We can attribute the increase in error as flow rate increased due to the increase in wall friction on the test vial. We can minimize this by increasing the size of our bench scale experiments.
#2) Sand Properties Parameters: We might have used an incorrect D60 and porosity for the filter bed in our equations. We tested this in our Mathcad code and found that if we increased the porosity from 0.4 to 0.5, the graph changed to Figure 3, thereby decreasing the error at %30 expansion to only 30% error:
Figure 3: Fluidization Velocity Experiment-porosity change
Then we also found that if we instead increased the d60 from 0.55 to 0.9, the graph changed to Figure 4, thereby decreasing the error at 30% expansion to only 16.7% error:
Figure 4: Fluidization Velocity Experiment-d60 change
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