Research On The Temperature Measurement Method Of Explosion Flame Based On Atomic Emission Spectrum

The temperature field distribution of the explosive flame characterizes the thermal damage performance of the explosive.The explosion is transient,and the harsh temperature measurement environment of high temperature,high pressure and strong impact is easy to cause the destruction of the test equipment,which puts forward more demanding requirements for the high temperature flame temperature measurement technology.Based on these problems,the atomic emission bisspectral method is used to measure the flame temperature.Put forward a new type all fiber structure modulation spectrum acquisition system transformation type,through the analysis of the multimode optical fiber interference theory,chose single-mode and multimode optical fiber structure as a spectrum spectral components,its principle is to use the reconstruction algorithm to resume the spectral information in the speckle pattern,at the same time,this paper proposes a genetic and simulated annealing algorithm to optimize the spectrum signal.It is verified that the length of the multi-mode optical fiber spectral system of 30 meters can distinguish two spectral lines separated by only6 pm,which shows that it has a very high resolution and can accurately reconstruct the sparse spectrum and the continuous spectrum with a certain bandwidth.On the basis of the high resolution spectrum acquisition system,a set of temperature measurement scheme is designed.Since the optical fiber can be rolled into a small volume,the miniaturization of the temperature measurement system is realized.Then the characteristic spectrum of the temperature measurement element is obtained by the optiBPM simulation software,and the intensity ratio error is 3%,which indicates the feasibility of the system.In addition,a temperature measuring system based on diffraction grating is designed,which USES the whole photosensitive array of the detector to obtain the two-dimensional temperature field.The whole set of device makes use of the design of window opening ofscanning mirror to make the system installed in the ground and avoid the damage of explosion to the measuring instrument.Moreover,the optical path is simulated and optimized with ZEMAX software,which makes the design more reasonable.In the process of wavelength calibration,five-point three-time smoothing algorithm is used to improve the spectral quality.Finally,the temperature field test of pulverized coal-butane mixed flame was carried out,and the temperature range of 490?~1489? was obtained.