Profiling and Characterization of Flame Radicals by Combining Spectroscopic Imaging and Neural Network Techniques

This paper presents the development of an instrumentation system for visualizing and characterizing free radicals in combustion flames. The system combines optical splitting, filtering, intensified imaging and image processing techniques for simultaneous and continuous monitoring of specific flame radicals ( OH*, CN*, CH*, and C2*). Computing algorithms are developed to analyze the images and quantify the radiative characteristics of the radicals. Experimental results are obtained from a gas-fired combustion rig to demonstrate the effectiveness of the system. The information obtained by the system is used to establish relationships between radical characteristics and air-to-fuel ratios of combustion gases, helping to obtain an in-depth understanding of burn characteristics.

[1]  Mário Costa,et al.  A NOx diagnostic system based on a spectral ultraviolet/visible imaging device , 1999 .

[2]  Cristiane Aparecida Martins,et al.  CH and C2 radicals characterization in natural gas turbulent diffusion flames , 2005 .

[3]  Sébastien Candel,et al.  Combustion control and sensors: a review , 2002 .

[4]  S. Cheskis.  Quantitative measurements of absolute concentrations of intermediate species in flames , 1999 .

[5]  Yong Yan,et al.  A digital imaging based multi-functional flame monitoring system , 2003, Proceedings of the 20th IEEE Instrumentation Technology Conference (Cat. No.03CH37412).

[6]  R. Bombach,et al.  Simultaneous visualisation of transient species in flames by planar-laser-induced fluorescence using a single laser system , 1999 .

[7]  J. Edward Jackson,et al.  A User's Guide to Principal Components: Jackson/User's Guide to Principal Components , 2004 .

[8]  M. Q. McQuay,et al.  Systematic measurements of OH chemiluminescence for fuel-lean, high-pressure, premixed, laminar flames , 2001 .

[9]  J.B. Fedison,et al.  Determination of Lean Burn Combustion Temperature Using Ultraviolet Emission , 2008, IEEE Sensors Journal.

[10]  Y. Mizutani,et al.  Processing of Luminescent Radical Images for Flame Diagnostics , 1989 .

[11]  J. Edward Jackson,et al.  A User's Guide to Principal Components. , 1991 .

[12]  Donald J. Patterson,et al.  In-cylinder measurement of mixture maldistribution in a L-head engine , 1995 .

[13]  Javier Ballester,et al.  Diagnostic techniques for the monitoring and control of practical flames , 2010 .

[14]  Mohammad Bagher Menhaj,et al.  Training feedforward networks with the Marquardt algorithm , 1994, IEEE Trans. Neural Networks.

[15]  M. G. Allen,et al.  An imaging neural network combustion control system for utility boiler applications , 1993 .

[16]  Fei Wang,et al.  The research on the estimation for the NOx emissive concentration of the pulverized coal boiler by the flame image processing technique , 2002 .

[17]  K. Kubica,et al.  The combustion of coal and biomass in a fixed bed furnace , 2002 .

[19]  Okyay Kaynak,et al.  An algorithm for fast convergence in training neural networks , 2001, IJCNN'01. International Joint Conference on Neural Networks. Proceedings (Cat. No.01CH37222).

[20]  A. G. Gaydon.  The spectroscopy of flames , 1957 .

[21]  J. E. Jackson.  A User's Guide to Principal Components , 1991 .

[22]  Yoshihiro Deguchi,et al.  Industrial applications of temperature and species concentration monitoring using laser diagnostics , 2002 .

[23]  Nick G Glumac,et al.  Flame Emission Spectroscopy for Equivalence Ratio Monitoring , 1998 .

[24]  Y. Hardalupas,et al.  Local measurements of the time-dependent heat release rate and equivalence ratio using chemiluminescent emission from a flame , 2004 .

[25]  Yannis Hardalupas,et al.  Chemiluminescence sensor for local equivalence ratio of reacting mixtures of fuel and air (FLAMESEEK) , 2004 .

[26]  Huaichun Zhou,et al.  A simple measurement method of temperature and emissivity of coal-fired flames from visible radiation image and its application in a CFB boiler furnace , 2009 .

[27]  Yong Yan,et al.  Impact of co-firing coal and biomass on flame characteristics and stability , 2008 .