This study was conducted to investigate the characteristics of meso-scale combustion.The technique of electrical capacitance tomography(ECT) was used to locate flame position and monitor the effect corresponding to va...This study was conducted to investigate the characteristics of meso-scale combustion.The technique of electrical capacitance tomography(ECT) was used to locate flame position and monitor the effect corresponding to varied air/fuel ratio in a meso-scale combustor.Combustion phenomena including igniting,quenching and unsteady combustion have been visualized using ECT.The method of metallization protecting ECT sensor from high temperature damage and the novel calibration method adapted to ECT monitoring of unknown permittivity flame have been shown to be successful.At the same time,electrical nature of combustion and dielectric characteristics of hy-drocarbon flame were studied.The relationship between flame permittivity and state parameters of combustion gas was demonstrated preliminarily.展开更多
Monitoring and control of combustion flames in utility boilers are required in order to optimize combustion conditions.This paper presents an instrumentation system for the concurrent measurement of the temperature di...Monitoring and control of combustion flames in utility boilers are required in order to optimize combustion conditions.This paper presents an instrumentation system for the concurrent measurement of the temperature distributionand soot concentration of flames developed on the two-color principle. This system consists of an endoscope,an optical assembly with optical filters, a CCD camera, a frame grabber and associated image processingsoftware. Experiments are performed on a methane-air combustor and the temperature fields and the soot concentrationscorresponding to the flame images are obtained. The results have demonstrated that the system is capableof performing on-line measurement of flame and temperature distribution, providing temporal and spatial characterizationof the combustion process. In addition, the combination of advanced optical sensing and digital imageprocessing technique can help to define the threshold by the analysis of the background noise. Furthermore, theutilization of the filter technique can enhance the image presentation effect to an extent.展开更多
基金Supported by the National Natural Science Foundation of China (50806005,50736002,61072005)
文摘This study was conducted to investigate the characteristics of meso-scale combustion.The technique of electrical capacitance tomography(ECT) was used to locate flame position and monitor the effect corresponding to varied air/fuel ratio in a meso-scale combustor.Combustion phenomena including igniting,quenching and unsteady combustion have been visualized using ECT.The method of metallization protecting ECT sensor from high temperature damage and the novel calibration method adapted to ECT monitoring of unknown permittivity flame have been shown to be successful.At the same time,electrical nature of combustion and dielectric characteristics of hy-drocarbon flame were studied.The relationship between flame permittivity and state parameters of combustion gas was demonstrated preliminarily.
基金the National High Technology Research and Development of China (863 Program) (2006AA05A103)the National Natural Science Fund (grant No. 40501017, grant No. 50706053)
文摘Monitoring and control of combustion flames in utility boilers are required in order to optimize combustion conditions.This paper presents an instrumentation system for the concurrent measurement of the temperature distributionand soot concentration of flames developed on the two-color principle. This system consists of an endoscope,an optical assembly with optical filters, a CCD camera, a frame grabber and associated image processingsoftware. Experiments are performed on a methane-air combustor and the temperature fields and the soot concentrationscorresponding to the flame images are obtained. The results have demonstrated that the system is capableof performing on-line measurement of flame and temperature distribution, providing temporal and spatial characterizationof the combustion process. In addition, the combination of advanced optical sensing and digital imageprocessing technique can help to define the threshold by the analysis of the background noise. Furthermore, theutilization of the filter technique can enhance the image presentation effect to an extent.
