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Show The use of modelling to solve real industrial problems is not new having been used since the beginning of the industrial age. Its use for solving combustion, heat transfer and process problems has expanded from the 1940's to the significant role it enjoys today. Provided that its limitations are recognized and respected, it is a cost effective way of meeting many industrial requirements. However, despite the success of modelling, and the cost savings and improved safety enjoyed by those who use it, it is still applied to only a minority of processes, and many industrial problems persist which could be resolved or prevented by the use of appropriate modelling techniques. Whilst zone mathematical modelling and CFD modelling are making valuable contributions to the understanding of industrial problems, physical modelling will have a role to play for many years, owing to its ease of application and previous widespread validation. There is no doubt that CFD modelling will continue to develop rapidly and become more user friendly, cheaper to buy and use, and be effectively validated for a wider range of problems. It will increasingly displace physical modell ing which, for the present, will continue to be more cost effective for many solutions. The other area of modelling which requires considerable development and validation to provide realistic answers for industrial problems, is NOx prediction. At present, the models available are useful for predicting the qualitative effects of changes for a limited number of systems, but there is considerable difficul ty in applying the models to al terna ti ve systems or obtaining reliable quantitative results. I look forward to the day (probably many years away) when we can convert our engineering general arrangement drawing to a CFD model by simply indicating the entry flows and conditions and not having to build a grid - CFD modelling will then have replaced physical modelling because it will be easier and cheaper! For the foreseeable future, it will often be necessary to undertake physical and mathematical modelling together, since each gives only part of the answer. REFERENCES 1. Thring, M.W. and Newby, M.P., Combustion Length of Enclosed Turbulent Jet Flames. 4th Symp. (Int.) on Combustion, 1953, 789 to 796 (Williams and Wilkins), Baltimore. 2. Holden, C., Combustion and Heat Transfer in the Open Hearth Furnace, Glass Technology Vol. 1, No.6, Dec. 1960, pp. 251, 259. 3. Moles, F.D., Watson, D. and Lain, P.B., The Aerodynamics of the Rotary Cement Kiln, 4th Symp. on Flames and Industry, London 1972. 4. Associated British Combustion - Private Communication. 5. Air/Water Analogue Model Tests, Hamworthy Combustion Internal R&D Report, October 1969. 6. Hawthorne, W.R, The Mixing of Gas and Air in Flames, ScD Thesis, 1939 (MIT Cambridge) • . |