An optical fiber liquid level sensor and its measuring method

Abstract

The invention discloses an optical fiber liquid level sensor and a measuring method thereof. The optical fiber liquid level sensor comprises an elastic wafer, a threaded cylinder, an incident optical fiber and a receiving optical fiber, wherein the elastic wafer is stuck on the bottom part of the cylinder; the incident optical fiber and the receiving optical fiber are symmetrically stuck on the elastic wafer along the diameter direction; a gap is formed between the incident optical fiber and the receiving optical fiber. The optical fiber liquid level sensor and the measuring method have the beneficial effects that influence factors of liquid density variation and accelerated velocity on liquid level measurement can be eliminated, so that more accurate liquid level information is obtained. According to the optical fiber liquid level sensor, the liquid level information is measured in a non-contact manner, so that the measurement is not restricted by properties of to-be-measured liquid, the possibility of explosion risk caused by electric sparks generated due to electrical measurement is prevented, therefore the anti-explosion performance is realized; meanwhile, a sensing part is easily installed, the price is low, the situation that the sensing part of the optical fiber sensor is polluted by the liquid is prevented, the stability of the sensor in the measurement process is guaranteed to a certain extent, and the electromagnetic interference resistance performance is good.

Description

Technical field: [0001] The invention belongs to the technical field of sensors, in particular to an optical fiber liquid level sensor and a measuring method thereof. Background technique: [0002] At present, the research on optical fiber liquid level sensors mainly includes optical fiber microbending liquid level sensors, optical fiber F-P cavity liquid level sensors, and optical fiber grating liquid level sensors. The optical fiber microbend sensor needs to design movable teeth and fixed teeth. When under pressure, the elastic diaphragm drives the movable teeth to move towards the fixed teeth, causing the optical fiber to bend slightly. Its advantage is that the measurement accuracy is high, and the disadvantage is that the deformation teeth Difficult; the optical fiber F‐P cavity liquid level sensor is designed according to the principle of the F‐P cavity interferometer. The F‐P cavity is usually composed of an elastic diaphragm and an optical fiber end face. It has the ...

AI Technical Summary

Problems solved by technology

The optical fiber microbend sensor needs to design movable teeth and fixed teeth. When under pressure, the elastic diaphragm drives the movable teeth to move towards the fixed teeth, causing the optical fiber to bend slightly. Its advantage is that the measurement accuracy is high, and the disadvantage is that the deformation teeth Difficult; the optical fiber F‐P cavity liquid level sensor is designed according to the principle of the F‐P cavity interferometer. The F‐P cavity is usually composed of an elastic diaphragm and an optical fiber end face. It has the advantage of simple structure, but it needs to consider temperature, light source The impact of strong changes on the measurement accuracy; the fiber grating liquid level sensor obtains pressure information through the modulation of the liquid pressure on the center wavelength of the grating. Its advantages are high measurement accuracy and easy to form a distributed measurement system. Its disadvantage is the wavelength demodulation equipment Expensive, need to solve problems such as desensitization

Images