This paper originally investigates the effect of NH_(3) dilution on soot formation when NH_(3) is gradually added into the fuel stream in an ethylene laminar diffusion flame stabilized on a Santoro burner.The variatio...This paper originally investigates the effect of NH_(3) dilution on soot formation when NH_(3) is gradually added into the fuel stream in an ethylene laminar diffusion flame stabilized on a Santoro burner.The variations of flame diameter and two flame heights,i.e.,mixture-strength flame height and visible flame height are carefully documented and analyzed.Moreover,local soot volume fraction(SVF)and soot temperature fields are simultaneously measured by compact-modulated absorption and emission technique,and the corresponding measurement random errors are also provided by the error propagation calculations for the first time.All the reported measurement random errors of SVF and soot temperature fields are estimated within the range of±0.07–±0.08 ppm and±40–±91 K,respectively.As an original database,the concomitantly measured SVF and soot temperature distributions are provided as high-fidelity datasets for refining soot formation model that is overrode by NH_(3).In addition,the flame cross-section average SVF F_(soot)(z)is calculated for every NH_(3) diluted flame,and the relative contributions of NH_(3) dilution and chemical effect are quantitatively assessed in terms of F_(max)-X_(NH_(3))plotting.It is found that when X_(NH_(3))<30%,the chemical effect of ammonia is about twice that of the dilution effect.While X_(NH_(3))>30%,the chemical effect and dilution effect of ammonia are gradually equal.Eventually,through modeling of the soot formation rate V in the flames,the relative contributions of chemical effect,dilution effect and thermal effect of NH_(3)are further novelty discriminated within the X_(NH_(3))from 0 to 46%and it is shown that NH_(3) chemical effect plays the dominate role in soot suppression,then the dilution effect and the thermal one at the least.展开更多
基金supported by the National Natural Science Foundation of China (Grant No.52130605)。
文摘This paper originally investigates the effect of NH_(3) dilution on soot formation when NH_(3) is gradually added into the fuel stream in an ethylene laminar diffusion flame stabilized on a Santoro burner.The variations of flame diameter and two flame heights,i.e.,mixture-strength flame height and visible flame height are carefully documented and analyzed.Moreover,local soot volume fraction(SVF)and soot temperature fields are simultaneously measured by compact-modulated absorption and emission technique,and the corresponding measurement random errors are also provided by the error propagation calculations for the first time.All the reported measurement random errors of SVF and soot temperature fields are estimated within the range of±0.07–±0.08 ppm and±40–±91 K,respectively.As an original database,the concomitantly measured SVF and soot temperature distributions are provided as high-fidelity datasets for refining soot formation model that is overrode by NH_(3).In addition,the flame cross-section average SVF F_(soot)(z)is calculated for every NH_(3) diluted flame,and the relative contributions of NH_(3) dilution and chemical effect are quantitatively assessed in terms of F_(max)-X_(NH_(3))plotting.It is found that when X_(NH_(3))<30%,the chemical effect of ammonia is about twice that of the dilution effect.While X_(NH_(3))>30%,the chemical effect and dilution effect of ammonia are gradually equal.Eventually,through modeling of the soot formation rate V in the flames,the relative contributions of chemical effect,dilution effect and thermal effect of NH_(3)are further novelty discriminated within the X_(NH_(3))from 0 to 46%and it is shown that NH_(3) chemical effect plays the dominate role in soot suppression,then the dilution effect and the thermal one at the least.
