To measure the flow, do this

Place the measuring tube on the top of the basket holding with one hand. Be careful not to block the discharge flow at the open top of the reactor. 

Turn the flow meter to the lower range and insert it in the side hole on the measuring tube to take readings. Move and turn the sensor slightly to be sure to get the highest reading. Record it. 

Repeat everything at every thousand RPM, switching the instrument to the higher range when needed. 

After the reading at the highest RPM, repeat the series once more. 

Remember diameters of the measuring tube and basket are different. Correct the linear velocity in the basket by reading the area differences. 

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