Ultrasonic flowmeter verification system and verification method

摘要

PROBLEM TO BE SOLVED: To provide a verification method of ultrasonic flowmeter that can enhance the reliability of the measurement accuracy of feed water flow rate by a propagation time difference type ultrasonic flowmeter, thereby reducing estimated errors in thermal output operations to improve the operating efficiency of a plant.SOLUTION: A target piping portion where an ultrasonic flowmeter is installed is three-dimensionally divided by meshes. A fluid analysis is conducted to obtain flow rates at respective mesh portions including an ultrasonic propagation passage part. The difference between an average flow rate obtained from the fluid analysis result at the ultrasonic propagation passage part and an average flow rate obtained by the propagation time difference of the ultrasonic at the ultrasonic propagation passage part. The difference between the two average flow rates is compared, as an ultrasonic propagation error, with an analysis permissible error. When the difference is over an analysis permissible error range, the difference between the average flow rates is obtained again after the meshes are made finer. When the difference is within the analysis permissible error range, the ultrasonic propagation error is evaluated.