Optical fiber gas concentration detection method with temperature compensation capacity

A technology for gas concentration detection and temperature compensation, which is used in the measurement of color/spectral characteristics to improve detection accuracy and reduce measurement errors.

Inactive Publication Date: 2015-11-18
NO 719 RES INST CHINA SHIPBUILDING IND
View PDF5 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

How to determine the characteristics of the gas absorption line changing with the temperature of the measurement environmen

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Optical fiber gas concentration detection method with temperature compensation capacity
  • Optical fiber gas concentration detection method with temperature compensation capacity
  • Optical fiber gas concentration detection method with temperature compensation capacity

Examples

Experimental program
Comparison scheme
Effect test

example

[0072] Differential absorption detection systems based on existing two-electrode DFBLD, such as figure 2 As shown, the signal generator generates a sine wave, and its output wavelength is modulated by adjusting the injection current of the laser. By changing the current ratio input by the two electrodes of the semiconductor laser, two optical signals with center wavelengths λ1 and λ2 are generated, λ2 is the reference light, and λ1 corresponds to the absorption peak of gas molecules, and the intensity is approximately equal. The light emitted from the DFBLD passes through the optical isolator to the fiber coupler, and the light coupled into the fiber is divided into two beams by the beam splitter. One beam of light passes through the reference gas chamber to the PIN detector, and the PIN output signal is phase-locked and amplified. It is used to feed back the injection current of the laser and stabilize the output frequency of the laser; another beam of light passes through t...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides an optical fiber gas concentration detection method with temperature compensation capacity. The method comprises specific steps as follows: step one, a laser device generates two optical signals, and central wavelengths of the two optical signals are lambda 1 and lambda 2 respectively; step two, each optical signal is split into two beams by an optical splitter after being transmitted through an optical fiber and then passes through a reference gas chamber storing reference gas and a detection gas chamber storing to-be-detected gas; step three, the spectral line intensity of light emitted from the reference gas chamber and the detection gas chamber is measured for multiple times; step four, the spectral line intensity is subjected to linear fitting, and temperature influence fitting coefficients of monochromatic light absorption coefficients of two wavelengths are obtained; step five, the gas concentration after temperature compensation is calculated according to the fitting coefficients. According to the method, a temperature compensation model of an optical fiber gas detection system is built, the optical fiber gas detection system considering temperature change factors is realized, interference of environmental temperature change to detection is inhibited in a temperature compensation manner, measurement errors caused by environmental temperature change are reduced, and the detection precision of the system is improved.

Description

technical field [0001] The invention relates to a gas concentration detection method, in particular to a gas concentration detection method with temperature compensation capability, and belongs to the technical field of optical fiber detection. Background technique [0002] Industrial field operations are usually carried out under the environmental conditions of high temperature, high moisture, high dust, strong corrosion and high flow rate. The continuous, reliable and safe development of on-site operations especially depends on the rapid and accurate detection of gas concentration. [0003] Although traditional non-optical gas detectors can achieve lower detection limits, they are easily cross-sensitized by other gas components, and their response speed is slow, their reusability is low, their service life is short, and it is difficult to detect continuously in real time . In order to overcome these defects, semiconductor laser absorption spectroscopy technology (TDLAS te...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G01N21/39
Inventor 阎毓杰王楠陈佳耿伟智杨云涛
Owner NO 719 RES INST CHINA SHIPBUILDING IND
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap