Experimental and computational investigation of temperature effects on soot mechanisms

Autor: Xinqi Qiao, Maoyu Xiao, Liu Yu, Xiaojie Bi, Chia-Fon Lee
Rok vydání: 2014
Předmět:
Zdroj: Journal of the Serbian Chemical Society, Vol 79, Iss 7, Pp 881-895 (2014)
ISSN: 1820-7421
0352-5139
DOI: 10.2298/jsc130614125b
Popis: Effects of initial ambient temperatures on combustion and soot emission characteristics of diesel fuel were investigated through experiment conducted in optical constant volume chamber and simulation using phenomenological soot model. There are four difference initial ambient temperatures adopted in our research: 1000 K, 900 K, 800 K and 700 K. In order to obtain a better prediction of soot behavior, phenomenological soot model was revised to take into account the soot oxidation feedback on soot number density and good agreement was observed in the comparison of soot measurement and prediction. Results indicated that ignition delay prolonged with the decrease of initial ambient temperature. The heat release rate demonstrated the transition from mixing controlled combustion at high ambient temperature to premixed combustion mode at low ambient temperature. At lower ambient temperature, soot formation and oxidation mechanism were both suppressed. But finally soot mass concentration reduced with decreasing initial ambient temperature. Although the drop in ambient temperature did not cool the mean in-cylinder temperature during the combustion, it did shrink the total area of local high equivalence ratio, in which soot usually generated fast. At 700 K initial ambient temperature, soot emissions were almost negligible, which indicates that sootless combustion might be achieved at super low initial temperature operation conditions.
Databáze: OpenAIRE