New float flowmeter

Abstract

A new float flowmeter design is presented based on the nuli method, with electric output signal and either manual or automatic current control in a coil to bring the float back to zero position. The instrument concerned is a constriction-type device and based on its theory a simple expression can be derived for describing the input-output relationship in quadratic terms. In addition to a description of the device, the static calibration curves using air at 295.16 ± 0.50 K are also provided for volumetric flowrates ranging from 11 to 16 dm 3 /min and Reynolds numbers between 500 and 800. Typical inaccuracy is 1.8% offlowrate over this range.

The Effects of Fluid Viscosity on the Orifice Rotameter

“…Through experiments he found that the outflow coefficient of the newly designed rotameter fell within a wide range of Reynolds numbers (minimum to 50) that remained constant, showing that viscosity has less influence on this rotameter. Vallascas [6] developed the magnetic suspension rotameter. An electric solenoid was installed in the outer conical tube to keep the float in a fixed position.…”