Abstract: An existing problem in the dry calibration method for the ultrasonic flowmeter is the effect of installation position of ultrasonic probe on the flow measurement. In order to solve this problem, a numerical simulation method based on computational fluid dynamics is proposed. Firstly, experiments are carried out to study the quantitative effect of ultrasonic flowmeter probe position on measurement. And the simulation model is created and optimized based on experiment results. Secondly, two typical installations—protrusion and recess— are discussed respectively. Through analyzing the flow mechanism of flow field, the velocity distribution along each acoustic path, and the variation of flow field at the probe, the effect law of probe installation position on the flow measurement and the produced measurement errors are obtained. Comparison between the two installation positions shows that the probe protrusion achieves a better measurement result, so it is recommended as an optimal installation position.

Key words: Dry calibration, Numerical simulation, Ultrasonic flowmeter, Ultrasonic probe