Fiber Bragg Grating Thermal Conductivity Of Carbon Dioxide Analyzer

In the modern social production and life,Gas composition testing play a very important role. There are many types of gas analyzer. Common analyzers include thermal gas analyzer, electrochemical gas analyzer, infra.red absorption type analyzer and gas chromatograph etc.Thermal conductivity type optical fiber,which is named Bragg grating Carbon dioxide analyzer designed in this paper is transfer the different heat transfer ability of mixed gas, whose CO2volume percent content is different to the different shift of Center wavelength of optical fiber Bragg grating. Through the test of the different shift of Center wavelength of optical fiber Bragg grating to realize the measurement of CO2volume percent content. This main research content of this article is as follows:1)On the basis of the principle of thermal conductivity, by using the sensitiveness of optical fiber Bragg grating to temperature,we have designed a kind of optical fiber Bragg grating sensor, which may used to test volume percent content level of carbon dioxide. And we have built the mathematical relationship between the amount of Wavelength shifting of optical fiber Bragg grating and volume percent content level of carbon dioxide.2)Finished machining and assembly of the component parts of the sensor, and finished the sealing and heat preservation processing of the sensor.3)Carried out the temperature calibration experiment by using the refrigerating constant temperature trough to optical fiber Bragg grating and optical fiber grating thermometer of the sensor. We have made the fitting analysis of the experimental data by using matlab and and calculated the static performance specifications of the optical fiber Bragg grating:the nonlinear error is0.54%FS, the sensitivity is8.3pm/℃, the sluggish is4.86%FS, the repeatability error is0.538%FS. The static performance specifications of optical fiber; grating thermometer are:the nonlinear error is0.625%FS, the sensitivity is9.5pm/℃, the sluggish is3.41%FS, the repeatability error is0.613%FS.4)Carried out sensor test experiment. Gaining the fitting curve between the Center wavelength of optical fiber Bragg grating and volume percent content level of carbon dioxide by using the matlab and based on the experimental data. And through this way, we have realized the test of volume percent content level of carbon dioxide.