Before a rotameter can be used to measure an unknown

Before a rotameter can be used to measure an unknown flow rate, a calibration curve of flow rate versus rotameter reading must be prepared. A calibration technique for liquids is illustrated below. A flow rate is set by adjusting the pump speed; the rotameter reading is recorded, and the effluent from the rotameter is collected in a graduated cylinder for a timed interval. The procedure is carried out twice for each of several pump settings.

(a) Assuming the liquid is water at 25oC, draw a calibration curve of mass flow rate, m (kg/min), versus rotameter reading, R, and use it to estimate the mass flow rate of a water stream for which the rotameter reading is5.3.


Rotameter Collection Volume Reading Collected (cm') Time (min) 2 297 2 301 4 454 4 448 ROTAMETER 0.5 0.5 300 298 STOPWAT