Ultrasonic probes and echo time algorithms in ultrasonic gas flow measurement systems: Progress and perspectives

Ultrasonic gas flowmeters employ non-intrusive measurement techniques, characterized by rapid responsiveness and exceptional anti-interference capabilities. These attributes not only minimize disruption to the gas during measurement but also facilitate dynamic process control while ensuring robust performance under complex operational conditions. This paper provides an overview of the key components of ultrasonic gas measurement systems, briefly summarizing the fundamental principles of commonly used measurement methods. After focusing on the evolution of transducer structures and materials within ultrasonic probes, it categorizes different types of transducers and outlines the latest designs of excitation circuits in both hardware and software. The review also critically assesses the determination of echo signal reception characteristics and the accuracy and effectiveness of time-of-flight calculations. Based on innovative analyses of the critical nodes within the measurement system's components, a framework system is established for corresponding measurement scenarios. The measurement results show that the repeatability error of the new transducer remains below 0.3%. The optimized signal processing method expands the measurable flow range to 30–1200 m3/h, and the zero drift is reduced to approximately half of the system's original zero drift. This paper aims to provide clear guidance for researchers and professionals in related industries, enabling them to conduct more in-depth studies based on their research interest and enhancing their understanding of ultrasonic measurements.