Ray-tracing simulation of sound drift effect for multi-path ultrasonic high-velocity gas flow metering

Claas Hartmann,Matthias Rutsch,Christoph Haugwitz,Mario Kupnik,Jan Hinrichs,Johannes Brotz,Dieter Bothe,Gianni Allevato,Peter Pelz

doi:10.1109/ius52206.2021.9593898

Abstract

Ultrasonic flow meters (UFMs) have the advantage of noninvasive flow metering of liquids, gases and multi-phase mixtures with or without particles. However, one challenge is a restricted measurement range of UFMs. The sound drift effect is causing a significant reduction of the signal to noise ratio (SNR) at larger flow velocities. In this paper, we extend our previous work by providing ray-tracing simulation of the sound drift effect for high flow velocities to predict the compensation angles and therefore increase the SNR, allowing measurements, of up to a flow velocity of 100 ms −1 in a pipe with a diameter of 31.5 cm, The 3D-ray-tracing calculation for each sound path of a multipath UFM takes into account the flow velocity distribution and the sound velocity within the flow meter. The pre-characterized velocity distribution is used in a boundary value problem, solving each sound ray path for a given compensation angle in flow velocity steps of 0.1 ms −1 . For validation, a 3D-printed flowmeter consisting of an 8 x 8, λ/2 phased-array for transmission and 14 individual single receivers for upstream and downstream sound paths are used. The correct steering angle maximizing the received power of the direct sound wave corresponds to the ideal compensation angle for each flow velocity and transducer. In general, the measured and simulated ideal compensation angles are in excellent agreement with a root mean square deviation of 2.88°. In upstream direction, the simulation no longer converges for flow velocities above 34.9 ms −1 for the outermost sound path above 78.9 ms −1 for the middle sound path.

Full Text