Inner arced ceiling thin wall straining cartridge throw-in type optical fibre Bragg grating pressure sensor

Abstract

An inner arc top thin wall strain cylinder drop-type optical fiber Bragg grating pressure sensor, belonging to the field of sensor technology, relates to a drop-type optical fiber Bragg grating pressure sensor for pressure measurement, characterized in that the inner side top of a metal thin wall inner cylinder is arc structured; both of the pressure-measuring optical fiber Bragg grating and the temperature compensating optical fiber Bragg grating are packaged in metallization; the pressure-measuring optical fiber Bragg grating is welded to the outer wall side of the metal thin wall inner cylinder axially with metal; the temperature compensating optical fiber Bragg grating is welded to the top outer side of the metal thin wall inner cylinder with metal; the pressure-measuring optical fiber Bragg grating is vertical to temperature compensating optical fiber Bragg grating to each other; two signal extraction single mode fibers are also packaged in metallization locally when passing through an optical fiber exit hole, and welded to the optical fiber exit hole with metal so as to close the optical fiber exit hole. The invention improves pressure-measuring range for a pressure sensor so as to solve the crossing sensitive problem of two Bragg gratings, which enhances operating temperature range for the sensor.

Description

technical field [0001] The invention belongs to the technical field of sensors, and relates to a novel drop-in optical fiber Bragg (Bragg) grating pressure sensor for liquid and gas pressure measurement. They are respectively welded on the side (circumferential direction) and top of the outer wall of the metal thin-walled inner cylinder of the structure in mutually perpendicular directions, which can solve the pressure / temperature cross-sensitivity problem and realize pressure measurement under high temperature conditions. Background technique [0002] Fiber Bragg grating is a special optical fiber in which the refractive index in the fiber core is permanently and periodically modulated. As a new type of passive optoelectronic device, it has good reliability, anti-electromagnetic interference, small size, light weight, and long life. Long, easy multiplexing / demultiplexing, long-distance transmission, corrosion resistance, and ability to work in complex and harsh environments...

AI Technical Summary

Problems solved by technology

[0004] Because the inner top of the inner tube of this fiber Bragg grating pressure sensor is a flat top structure, the corners of the top are prone to defects caused by excessive local pressure and damage, resulting in a small measurement range of the sensor, which cannot meet the needs of people for large pressure measurements. range of needs

And because the coupling glue used to stick the fiber Bragg grating to the thin-walled inner cylinder is usually a polymer glue, once the measurement environment temperature exceeds 100°C, this type of coupling glue will fail, making the sensor no longer able to measure accurately

In addition, the two fiber Bragg gratings pasted in parallel tend to interfere with each other, and the temperature compensation effect is not ideal

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