摘要
Particle image velocimetry （PIV）, thermocouples and flue gas analyzer are used to study swirling coal combustion and NO formation under different secondary-air ratios. Eulerian-Lagrangian large-eddy sim-ulation （LES） using the Smagorinsky-Lilly sub-grid scale stress model, presumed-PDF fast chemistry and eddy-break-up （EBU） gas combustion models, particle devolatilization and particle combustion models, are simultaneously used to simulate swirling coal combustion. Statistical LES results are validated by measurement results. Instantaneous LES results show that the coherent structures for swirling coal com- bustion are stronger than those for swirling gas combustion. Particles are shown to concentrate along the periphery of the coherent structures. Combustion flame is located in the high vorticity and high par-ticle concentration zones. Measurement shows that secondary-air ratios have little effect on final NO formation at the exit of the combustor.
Particle image velocimetry （PIV）, thermocouples and flue gas analyzer are used to study swirling coal combustion and NO formation under different secondary-air ratios. Eulerian-Lagrangian large-eddy sim-ulation （LES） using the Smagorinsky-Lilly sub-grid scale stress model, presumed-PDF fast chemistry and eddy-break-up （EBU） gas combustion models, particle devolatilization and particle combustion models, are simultaneously used to simulate swirling coal combustion. Statistical LES results are validated by measurement results. Instantaneous LES results show that the coherent structures for swirling coal com- bustion are stronger than those for swirling gas combustion. Particles are shown to concentrate along the periphery of the coherent structures. Combustion flame is located in the high vorticity and high par-ticle concentration zones. Measurement shows that secondary-air ratios have little effect on final NO formation at the exit of the combustor.
基金
supported mainly by the National Natural Science Foundation of China under the Grant 50606026
supported by the National Natural Science Foundation of China under the Grant 50736006
the Foundation of the National Key Laboratory of Engines,Tianjin University underthe Grant K-2010-07
