The English term for a flowmeter is, naturally, "flowmeter." The National Committee for Terms in Sciences and Technologies defines it as an instrument that indicates the measured flow rate and/or the total volume of fluid passing through it within a selected time interval. Simply put, it is a device used to measure the flow rate of a fluid within a pipeline or an open channel.
Flowmeters can be further categorized into various types, including differential pressure flowmeters, rotameters, throttling flowmeters, slit flowmeters, positive displacement flowmeters, electromagnetic flowmeters, and ultrasonic flowmeters. When classified by the medium being measured, they are broadly divided into liquid flowmeters and gas flowmeters.
Metrology serves as the "eyes" of industrial production. Flow measurement constitutes an integral part of metrological science and technology, maintaining close ties with the national economy, national defense construction, and scientific research. Executing this work effectively plays a vital role in ensuring product quality, enhancing production efficiency, and fostering scientific and technological advancement. This is particularly true in the modern era-characterized by energy crises and ever-increasing levels of industrial automation-where the status and significance of flowmeters within the national economy have become even more pronounced.
In engineering practice, the commonly used unit is m³/h. Flow can be broadly categorized into instantaneous flow rate and total flow. Instantaneous flow rate refers to the quantity of material passing through the effective cross-section of a closed pipe or open channel per unit of time; the flowing medium may be a gas, a liquid, or a solid. Total flow, conversely, represents the cumulative quantity of fluid passing through the effective cross-section of a closed pipe or open channel over a specific time interval (e.g., a day, a week, a month, or a year). Since total flow can also be derived by integrating the instantaneous flow rate over time, instantaneous flowmeters and total flowmeters are, in principle, mutually convertible.
