Trends in Improvement of Modern Ultrasonic Flowmeters

Abstract

Special measuring instruments — flowmeters — are used to measure the flowrates of various fluids moving in pipelines. In view of a large number of different requirements for flowmeters, various flow measurement methods have been developed and implemented, which are applied depending on the physicochemical properties of the fluid flowing through a pipe, requirements for metrological characteristics, and the simplicity of measuring device design and its maintenance. The ultrasonic measurement method is one of the most promising and intensely developing liquid flowrate measuring methods. It features high reliability and accuracy, ability to measure the flowrate of non-conducting fluids, and the possibility to perform measurements without upsetting the pipeline wall integrity. At the same time, the use of this method involves certain specific features and problems that are inevitably encountered by all developers of ultrasonic flowmeters. The article analyzes the main error components in the measurement results obtained using ultrasonic flow meters (such as the hydrodynamic error, time interval measurement error, error in measuring the difference of propagation times, etc.), examines the methods for improving their accuracy that are used in the modern ultrasonic flow meters, and discusses the ways of their further improvement. The study is primarily focused at reviewing the current state of the art in the development of this method and the possibilities for its further improvement, and providing some information about the major companies producing ultrasonic flowmeters, the instruments manufactured by them, and the applied design and circuit engineering solutions. The article is relevant for the readers who need information about the possibilities of ultrasonic flowmeters and about the prospects of using them, and who are striving to develop a high-precision ultrasonic flowmeter with improved metrological characteristics.