화학공학소재연구정보센터
Industrial & Engineering Chemistry Research, Vol.49, No.5, 2510-2520, 2010
Numerical Study of Isothermal Flow and Mixing Characteristics in a Cyclone-Jet Hybrid Combustor
The isothermal flow and mixing characteristics of a cyclone-jet hybrid combustor using a combination of cyclone premixed and jet diffusion flames were numerically investigated. The computational fluid dynamics model was validated with experimental results for a cyclone-jet premixed combustor. Good agreement was obtained between the simulated and experimental results. As a result, in the diffusion combustion (DC) mode, the cyclone now velocity played an important role on the development of swirling flow patterns, but the improvement of fuel-air mixing was limited due to low interaction between axial jet and cyclone flows. On the other hand, the fuel-air mixing characteristic in the hybrid combustion (HC) mode were significantly better than those for the DC mode. Through the modification of axial nozzle geometry, it was found that both the distributed fuel (DF) and multihole fuel (MF) nozzles provided improved fuel-air mixing compared to the single-fuel (SF) nozzle. Finally, it was confirmed with previous experimental results that the detailed understanding of complex flow structure and mixing phenomenon conducted in the present study was very useful for the advanced combustor design in terms of flame stability and pollutant emissions.