Publish Time: 2022-06-10 Origin: Site
Ultrasonic flowmeter is an instrument for measuring flow by detecting the effect of fluid flow on ultrasonic beam (or ultrasonic pulse).
According to the principle of signal detection, ultrasonic flowmeter can be divided into propagation velocity difference method (direct time difference method, time difference method, phase difference method and frequency difference method), beam offset method, Doppler method, cross-correlation method, spatial filtering method and noise method.
Like electromagnetic flowmeter, ultrasonic flowmeter is an unimpeded flowmeter because there are no obstacles in the instrument flow channel. It is a kind of flowmeter suitable for solving the difficult problem of flow measurement, especially in large-diameter flow measurement. It is one of the rapidly developing types of flowmeter.
(1) It can be used for non-contact measurement;
(2) No flow obstruction measurement and no pressure loss;
(3) It can measure non-conductive liquid, which is a supplement to the electromagnetic flowmeter without obstruction.
Disadvantages:
(1) The propagation time method can only be used to clean liquids and gases; The Doppler method can only be used to measure the liquid containing a certain amount of suspended particles and bubbles;
(2) The measurement accuracy of Doppler method is not high.
Application Overview:
(1) The propagation time method is applied to clean, single-phase liquids and gases. Typical applications include factory discharge liquid, strange liquid, liquefied natural gas, etc;
(2) In terms of gas application, it has good experience in the field of high-pressure natural gas;
(3) Doppler method is applicable to two-phase fluids with low heterogeneous content, such as untreated sewage, factory discharge liquid and dirty process liquid; Generally not suitable for very clean liquids.