Paper: Ultrasonic Flowmeters For Petrochemical Process Control

The flow of gaseous and liquid hydrocarbons is now routinely measured ultrasonically. Ultrasonics has taken some twenty years to prove itself in nonideal industrial petrochemical process control applications. It has now reached the stage where many users specify ultrasonics when they want to achieve reliable, accurate measurements without loss of pressure; linearity despite wide turndown ratios; no moving parts; wide temperature range; portability. The ultrasonic flowmeter output can in general be in units of velocity, volumetric or mass flowrate. This presentation covers basic contrapropagation theory; flow profile; flare gas molecular weight, density and mass flowrate determination; liquid clamp-on applications; and limitations of the technology.