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Show 15 In order to fully understand and characterize the phenomena involved, further experiments are planned using different atomizing gases, different fuel viscosities, different class of atomizers and burners. Nevertheless, the results clearly demonstrate the feasibility for realtime monitoring of the atomization quality. 4 GENERAL CONCLUSION This paper addresses some aspects of the development of fuel oil burners dedicated to oxycombustion, at Air Liquide. A short description of the phenomena involved in liquid atomization is given. The specificity of oxygen atomization or combustion are mentionned. Atomizer development is driven by industrial expectations. T w o series of atomizers developped at Air Liquide, the Dual and the Trident, are presented. The Dual is a very flexible atomizer (atomizing gas is air). The Trident generates low-NOx flat flames, the atomizing gas being air, oxygen or even steam. On-going development of a low pressure oxygen atomizer are also shown, the final objective being an atomizing oxygen pressure of 100-150 mbar to meet V S A specification. The second part of this paper focus on a novel concept for monitoring the quality of atomization. Maintenance is a particularly important issue in fuel oil combustion. The monitoring technique (previously applied to natural gas combustion) is successfully applied to fuel oil combustion. From the spectra of the flame, captured with a fiber optic probe, two lines are identified, the CH and the OH emission. From results obtained in the 2 M W pilot furnace available at Air Liquide, France, it is shown that a degradation in atomization quality is perfectly detectable using this technique. References Aftel, R., Gupta, A., Cook, C. and Presser, G., (1996) "Gas property effects on droplet atomization and combustion in an air-Assist atomizer", Twenty-Sixth Symposium (International) on Combustion, The Combustion Institute, pp. 1645-1651 Care, I. and Ledoux, M. (1991). "Study of an airblast coaxial atomizer, experiments and modelisation", In Proceedings of the 5th Int. Conf. on Liquid Atomization and Sprays, Rouen, France Dugue, J., Von Drasek, B., Samaniego, J.M., Charon, O. and Oguro, T. (1998) "Advanced Combustion facilities and diagnostics", AFRC/JFRC International Symposium, Hawaii Elkotb, M., Mahdy, M.A. and Montaser M.E. (1982) "Investigation of external-mixing airblast atomizers" in Proceedings of the 2n Int. Conf. on Liquid Atomization and Sprays, Madison, Wis. |