Research On Improved Image Reconstruction Methods Of Welding Flame Temperature Field Based On Incomplete Projection Data

For testing the developing level of industry and modern technology, the level of development of welding technology is an important sign, and temperature is the most important factor of welding technology. The measurement and control of temperature plays an important role in the national defense, military, scientific experiments and industrial and agricultural production, especially high temperature measurement places a very important position in aerospace, materials, energy, metallurgy and other fields. Therefore, the study of welding flame temperature field will be paid more extensive attention. Optical tomography technology has wide application prospects in temperature field testing, wind tunnel, asymmetry field, plasma parameter testing for its particular merit. The complete projection data is difficult to obtain during the actual operation, so the increasing concern of research on temperature field of non-completed data, asymmetry, non-steady has become the most challenging and attractive problem at home and abroad in this research field.This research provide a new technology which is used to diagnose oxyacetylene temperature field by using orthographic and double-wave light path; The technology adopting data testing system of spectrum intensity with two orthographic direction CCD image real-time collection to get the gray information of the Oxyacetylene flame , then reconstruct orthographic emission coefficient using self-adaptive relaxation-parameter simulated annealing reconstruction technique tomography algorithms(This algorithms show great superiority through compare with conventional tomography algorithms);Finally, we choose spectrum relatively intensity method to reconstruct temperature field distribution feature which based on oxyacetylene physical theory; This system can show space distributing of correlate physical parameter correctly by using new image processing technology. This method is beneficial to research the area of aerospace, missile and rocket engines and propellant production and help to measure some parameters such as thermal insulation material ablation rate, quality ablation rate, adiabatic exponent, and permeability. It is an irreplaceable method for carrying out optimization and filtration about scientific research, and controlling production quality.The innovation of this research is that the oxygen-acetylene welding flame is the testing target; design a temperature test system for using a series of telecentric lenses to receive parallel beam, improve the method of calibration ,reduce the loss of information and errors of reconstruction; Design a new algorithms adapt to orthographic projection data, and prove the feasibility of orthographic and double-wave light path through numerical simulation ,ultimately diagnose the temperature testing of oxyacetylene.