Study Of Gas Temperature Measurement Method Based On Spectrum Absorption

In recent years, China's aerospace undertakings and in the auto industry has achieved rapid development, which are related to the development of improved engine performance are inseparable. With the engine's heat load increasing, making contact with the gas piston, and other parts of the temperature rising, it is easy to produce all kinds of faults, accurately measuring the temperature of combustion gases, in order to raise the piston engine life. In addition, the measurement of the gas inside the engine temperature, its internal combustion situation in real-time monitoring and analysis in order to enhance the efficiency of the engine to provide an important parameter.Traditional industrial thermocouples , with fragile, short life expectancy, poor reliability and response time. In this paper, oxygen gas as a target, the absorption spectroscopy research based on the temperature measurement. The system has a response speed and temperature field of non-interference and high precision, small heat loss, corrosion-resistant, easy-to-control advantages of the anto industry to meet the gas engine combustion temperature measurement accuracy for high-temperature gas temperature measurement provides a new measurement program.In theory, the study analyzed the oxygen in the vicinity of the 760nm absorption lines, by selecting the appropriate gas absorption lines of its strong line of the ratio of temperature-sensitive function, and real-time measurement of gas temperature. Experiments in high-temperature experiment platform using vertical cavity surface emitting semiconductor laser (VCSEL), through the use of wavelength modulation spectroscopy gas absorption spectrum changes with temperature characteristics of oxygen absorption spectra of the second harmonic signal detection. Through the different lasers to change the modulation depth study on the impact of signal detection, the ultimate validation of the use of tunable diode laser absorption spectrometry technology for measuring the feasibility of gas temperature.The article discusses the tunable diode laser absorption spectroscopy of the basic principles of temperature measurement; before the laser experiment and how to choose a detector, as well as the operation of the laser Notes; temperature control box structure, as well as the basic working principle; for different gas temperature range, How to choose the correct measurement of the spectrum; based on absorption spectroscopy measurement of the temperature contrast; experimental system deficiencies point.