ISSN Online: 2377-424X
ISBN Print: 1-56032-797-9
International Heat Transfer Conference 11
FURNACE COMBUSTION AND HEAT TRANSFER IN LARGE UTILITY BOILERS
Sinopsis
The combustion of fossil fuels in a utility furnace is a
complex process involving turbulent gas dynamics,
multiphase solids-gas flow, chemical reactions, radiative
and convective heat transfer, and pollutant formation. With
the passage of the 1990 Clean Air Act Amendments in the
United States Congress, "traditional" ways of designing
furnaces based on semi-empiricism are being revised with
the aid of comprehensive analytical methods based on
fundamental principles. These new analytical methods are
utilized for furnace designs which accommodate modern
pollution abatement technologies such as low NOx burners,
staged/overfire air, flue gas recirculation, and reburning.
This paper presents the current status of technology
practiced by the boiler manufacturers for the predictions of furnace performance based on theoretical principles.
Mathematical formulations for the various combustion and
heat transfer processes and general numerical solution
techniques are presented, followed by example cases for
tangentially-fired, front wall-fired, front and rear wall-fired, cyclone-fired, and arch-fired furnaces. Limitations of the current knowledge bases and future research areas are indicated throughout the paper.