Three Dimensional Monitoring and Characterisation of Burner Flames Using Tomographic
Imaging Techniques
Phillip M. Brisley, Gang Lu, Yong Yan
Instrumentation, Control and Embedded Systems Research Group,
School of Engineering and Digital Arts, University of Kent, Kent CT2 7NT, UK.
Tel: +44 (0)1227 823015, email: y.yan@kent.ac.uk
Geometric, luminous and thermodynamic characteristics of the flames in combustion systems are
closely related to combustion efficiency and pollutant emissions as well as furnace safety.
Advanced instrumentation systems for quantitative monitoring and characterisation of flames have
therefore become a highly desirable tool in the drive towards ever cleaner and efficient large scale
combustion systems, and much research effort has been put to this end [1,2]. As part of an on-going
project funded by BCURA (British Coal Utilisation Research Association), a novel laboratory scale
prototype system for measuring 3D temperature distribution within a flame is now being developed.
The system hardware consists of eight imaging optical fiber bundles with associated coupling
lenses, two RGB CCD cameras, two frame grabbers and a personal computer with application
software. The system software implements a conjunction of digital imaging techniques, namely
reconstruction from projections, based on Radon transformation, and two colour pyrometry, to
reconstruct temperature sections through a flame from captured images. The system was calibrated
using a pre-calibrated tungsten lamp as a known temperature source.
To evaluate the performance of the prototype system and the effectiveness of the proposed
algorithms for determining the 3D temperature distribution of a flame, a series of experiments was
conducted. A small Bunsen burner flame was used for this investigation as it presents a steady
laminar flame with a high level of rotational symmetry making it ideal for evaluation of the
prototype system. The results show that the system is capable of determining the temperature
distribution within a simple flame to a reasonable accuracy using a minimum of hardware. Fig.1
shows the luminosity reconstruction of flame cross- and longitudinal-sections [3]. Future work will
be directed toward improving the spatial resolution of reconstructed temperature sections.
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(a) 2-D image.
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(b) Cross- sections.
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(c) Longitudinal-sections.
Fig.1 Luminosity reconstruction of flame cross- and longitudinal-sections
References
[1] Y. Huang and Y. Yan, ‘Transcient two-dimensional temperature measurement of open flames by duel
spectral image analysis’, Transactions of the Institute of Measurement and Control, vol.22, no.5,
pp.371-384, 2000.
[2] Y.Yan, G. Lu and M. Colechin, ‘Advanced monitoring and characterisation of pulverised coal flames’,
Fuel, vol.81, no.5, pp.647-656, 2002.
[3] H. C. Bheemul, G. Lu and Y. Yan, ‘3D visualisation and quantitative characterisation of gaseous
flames’, Meas. Sci. Technol., vol.13, no.10, pp.1643-1650, 2002.