PERCENTAGE DEVIATION BASED EVALUATION OF VELOCITY DEPENDENT CHARACTERISTICS IN ULTRASONIC FLOW METERING SYSTEMS

摘要

Apparatus and method for monitoring operation of an ultrasonic flow meter. In one embodiment, an ultrasonic flow metering system includes a passage for fluid flow, an ultrasonic flow meter, and a condition monitor. The ultrasonic flow meter is configured to measure transit time of an ultrasonic signal through the fluid flowing in the passage. The condition monitor is coupled to the ultrasonic flow meter and is configured to monitor a parameter of operation of the ultrasonic meter, and to acquire a plurality of values of the parameter over time. The condition monitor is also configured to compute, for each of the acquired values, a difference between the acquired value and a predetermined reference, and to arrange the differences in time sequence.