CO噴流拡散火炎における局所反応速度および拡散速度 : 熱工学,内燃機関,動力など

抄録

The local reaction rate and the diffusion rate are important parameters which dominate combustion phenomena in a turbulent diffusion flame, but they cannot be directly measured. Then, in the previous study, the present authors developed the method to obtain the reaction rate and the diffusion rate by numerical calculation using measured values for a hydrogen jet diffusion flame. In the present study this method was applied to a CO jet diffusion flame where the chemical reaction is comparatively simple and preferential diffusion may not be influential. The following results were obtained. (1) Effective diffusion coefficients D_C, D_O and D_N, which are obtained using respectively C, O and N elements as tracers, were almost the same to each other in the whole region of the flame. This seems to mean that, because the turbulent diffusion rate is sufficiently larger than the molecular diffusion rate, effective diffusion rates are nearly the same to all chemical species. (2) Then, the assumption, that Lewis number is 1 in the conserved scalar approach, is applicable to this CO flame. The present data may be useful in the examination of modeling methods of turbulent diffusion flames.