OCR Text |
Show 1. INTRODUCTION Nitrogen oxides are important air pollutants, believed to play a central role in the formation of photo-chemical smog and acid rain. The' nitrogen oxides are generated in high-temperature combustion processes and thus are released by stationary combustion sources , motor vehicles, as well as a wide range of domestic fossil fuel fired appliances. Recently, the emissions from these sources are legislated. Meeting the ever evolving standards continues to challenge available combustion technology. As a' result, the interest in predicting the formation of nitrogen oxides in practical combustion systems has become large. Unfortunately, the formulation of reliable, accurate models has been severely hampered by the absence of proper descriptions of, amongst others, turbulence-chemistry interactions, radical super equilibria, prompt, and fuel-NO chemistry. The availability of accurate, reliable, but mostly proper physical models can be an invaluable tool for evaluating potentially beneficial combustion options such as oxygen enrichment. The present paper describes a comprehensive model which addr ss s the Issues. After a brief description of the key £ atur s, th n1 d 1 is applied to an industrial-type burn r. it ts f air t Ing and oxygen enrichment are examined . (2) |