Question

1) If a rotameter is not level, is the reading it provides too high or too low? Why?

2) Is the float in a rotamter becomes dirty (accumulates mass over time), is the reading it provides too high or too low? Why?

3) Why is it important to submerge the tubing end before taking the initial rotameter reading?

Answer 1

1) If the rotameter( or we call it 'float') is not level, the reading would be too high as the effect of gravity will be low. If the instrument is not level, the friction on the float will be higher, resulting in a reading that is too low.

2) If the float in the rotameter becomes dirty, the space for the fluid to flow between the float and bore reduces which makes the same flow rate to cause higher fluid velocity so more drag on the dirty float. So the lift on the float goes up a lot faster than the mass of the float increases. So the reading is generally higher than actual.

3) It is important to submerge the turbing end before taking initial reading becuse this allows to calibrate the rotameter and determine the flowrate that we should be looking for in our readings.

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