Methane concentration distributed optical fiber detection system

Abstract

The invention provides a methane concentration distributed optical fiber detection system which is used for detecting methane in n air chambers. The system comprises a laser, an isolator,n-1 couplers,n-1 optical fiber delay lines, a light spot detector, and an acquisition processing module, wherein a first coupler of the n-1 couplers is connected with the isolator, a first coupler to an n-2th coupler of the n-1 couplers are connected with a first air chamber to an n-2th air chamber of the n air chambers in a one-to-one correspondence mode, and an n-1th coupler is connected with an n-1th air chamber and an nth air chamber of the n air chambers at the same time; the first to n-2th optical fiber delay lines in the n-1 optical fiber delay lines are used for connecting the n-1 couplers, and the n-1th optical fiber delay line is used for connecting the n-1th coupler and the nth air chamber; the light spot detector is connected with the first coupler and used for receiving pulsed light reflected by the air chamber to correspondingly obtain n detection pulses; and the acquisition processing module is connected with the photoelectric detector and is used for obtaining the spatial positionof the corresponding gas chamber according to the time position of the detection pulse and inverting methane gas concentration information in the corresponding gas chamber according to the absorptioncharacteristic of the detection pulse.

Description

technical field [0001] The invention relates to a methane detection system, in particular to a methane concentration distributed optical fiber detection system. Background technique [0002] Methane gas is a flammable and explosive gas. Under normal pressure, the explosion limit is 5%-15%, so its concentration must be reliably detected. There are many kinds of related technologies. Among them, the selective absorption characteristics of gas to the spectrum are used to detect the concentration by detecting the absorption. It has the characteristics of strong gas selectivity, high sensitivity, anti-interference, and can be used in special environments such as flammable and explosive. become a research hotspot in recent years. Especially with the development of semiconductor laser technology, using TDLAS technology, various miniaturized, low-cost, and practical methane detection systems have been commercialized, and related products have provided better solutions for coal mine...

AI Technical Summary

Problems solved by technology

Subsequently, researchers carried out research on multi-point detection technology based on TDLAS. However, most technical solutions use optical switches, splitters, etc. to form single-point sensors into a star topology to achieve multi-channel detection. When range pipeline detection is performed, the implementation of the star topology is limited, which affects the detection effect

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