Pipeline flow and liquid level monitoring instrument is an instrument that integrates flow and liquid level detection functions, used for real-time monitoring of medium flow and liquid level status in pipelines. It is widely used in fields such as water conservancy, chemical industry, municipal water supply, etc.
Pipeline flow and liquid level monitoring devices are usually based on various physical principles to measure flow and liquid level. Common principles include:
Ultrasonic principle: By utilizing the relationship between the propagation speed of ultrasonic waves in a fluid and the fluid flow velocity, the fluid flow velocity is calculated by measuring the time or frequency difference of ultrasonic wave propagation in the forward and backward directions, and then the flow rate is obtained. At the same time, the ultrasonic level gauge measures the time difference between the transmission and reception of ultrasonic waves by emitting ultrasonic pulses and receiving their reflected waves, and calculates the liquid level height.
Radar principle: The radar level gauge measures the time difference between the transmission and reception of microwaves by emitting microwave pulses and receiving their reflected waves, and calculates the liquid level height. Radar flow meters utilize the Doppler effect to calculate fluid velocity and flow rate by measuring the frequency changes of reflected waves.
Doppler effect: When ultrasound propagates in a fluid, if there are particles (such as suspended solid particles, bubbles, etc.) that move relative to the fluid, these particles will scatter the ultrasound, causing a change in the frequency of the scattered waves. By detecting and analyzing this frequency change, the flow velocity and flow rate of the fluid can be calculated.
Differential pressure principle: Differential pressure flowmeter works based on Bernoulli equation. It measures the static pressure difference generated when the fluid flows through a throttling device (such as orifice plate, nozzle, etc.), and calculates the fluid flow rate by combining the density of the fluid and the structural parameters of the throttling device. Differential pressure level gauge calculates the liquid level height by measuring the pressure difference between the bottom and top (or reference point) of the liquid.
According to different measurement principles and application scenarios, pipeline flow level monitoring instruments can be divided into the following types:
Ultrasonic pipeline flow level monitoring device: Combining the functions of ultrasonic flowmeter and ultrasonic level gauge, it is suitable for flow and level monitoring under various working conditions such as non full pipe and full pipe. It has the advantages of non-contact measurement, easy installation, and low maintenance cost.
Radar pipeline flow level monitor: Combining the functions of radar flowmeter and radar level gauge, it is suitable for flow and level monitoring in harsh environments such as high temperature, high pressure, and strong corrosiveness. It has the advantages of high measurement accuracy, good stability, and strong anti-interference ability.
Doppler pipeline flow level monitor: based on the Doppler effect to achieve flow measurement, and integrated with liquid level measurement function, suitable for fluid flow and liquid level monitoring containing suspended solid particles or bubbles. It has the advantages of wide measurement range, high accuracy, and low requirements for fluid cleanliness.
Differential pressure pipeline flow level monitor: Combining the functions of differential pressure flowmeter and differential pressure level gauge, it is suitable for scenarios that require high measurement accuracy and stable fluid properties. It has the advantages of high measurement accuracy and good stability, but is easily affected by factors such as fluid properties and pipeline installation conditions.