Research On Emission Spectral Tomography Based On The Radiation Balance Between Infinitesimal

The measurement and control of temperature plays an important role in the defense,military, scientific experiments or industrial and agricultural production, especially inaerospace design and development of engine. Engine combustion chamber which isclosed and not visible has high spout of the flow field and its temperature is very high,so the state of combustion chamber can only be shown by the temperature of engineexhaust plume. This shows the research of measurement of temperature distribution ofthe flow in the contemporary has a very important practical significance. However, dueto high temperatures, unstable and other characteristics of flow, it is difficult to measureit by conventional methods. In recent years, many scholars at home and abroad havemade some progress using computer image processing technology, optical tomographyand radiation temperature measurement means to determine the state of the flow fieldand temperature levels.In the measurement of the temperature field which has high temperature and isunstable, the projection collected by the target area array CCD surface is the ray whichtransporting in the flow field after the emission, absorption and scattering process. Thisthesis does a lot of research on the radiation transmission characteristics, the radiationtheory of blackbody and emission spectral tomography of the flow field and the methodof three-dimensional reconstruction of temperature field based on a multichannel singlespectral tomography is proposed which under the radiation balance between theinfinitesimal.To improve the accuracy of reconstruction temperature field, we consider theabsorption, emission and scattering characteristics of the radiation medium, theradiation projection matrix is derived and a model of three-dimensional reconstructionof temperature distribution is constructed under the relationship of balance betweeninfinitesimal, at the same time, the calibration methods to solve a set of absorption rateand absorption coefficient is designed. Combined with sophisticated computing ARTalgorithm which in CT, the model is simulated by MATLAB, by discussing theinfluence of a variety of factors of the accuracy in the reconstruction process, therelationship between various factors in reconstruction algorithm is given.A multiple single wavelength image acquisition system is also designed in thispaper, which is composed of telecentric lens, narrow-band optical filter, industrial area array CCD camera and image capture card. The system is implemented on a smallcandle flame field, three-dimensional temperature distribution of the candle flame isreconstructed well. The finally actual results show that the reconstruction model basedon the theory of balance between infinitesimal can be used on the temperature fieldreconstruction.