Selection of flow measurement method and instrument
The selection of flow measurement methods and instruments, the English name of the flowmeter is flowmeter, which is defined by the national committee on scientific and technical terms: indicating the measured flow rate and/or the total amount of fluid in a selected time interval.Simply put, it is a meter used to measure the flow of fluid in a pipe or open channel.
Flow measurement method
1. The velocity method USES the flow rate to measure the average flow rate of the fluid in the pipe, and then multiplicates the section area of the pipe to obtain the volume flow rate of the fluid.The flowmeter based on this method includes differential pressure flowmeter, rotor flowmeter, electromagnetic flowmeter and ultrasonic flowmeter.
2. Volumetric method is to continuously measure the flowing medium with a standard fixed volume per unit time, and calculate the flow rate with the fixed volume of the discharged fluid.The flowmeter based on this method is like ellipse gear flowmeter, piston flowmeter and scraper flowmeter.
3. Mass flow detection can be divided into direct method and indirect method.
Direct mass flowmeter directly measures mass flow rate, such as angular momentum type, calorimeter type and coriolis force type, etc. : indirect mass flowmeter measures volumetric flow rate and fluid density simultaneously and automatically calculates mass flow rate.
The measuring accuracy of mass flowmeter is not affected by temperature, pressure and density of fluid.