Flame structure of diesel surrogate combustion in a counterflow diffusion flame

EDGAR AGUILERA; RAUL GOMEZ; DARIO ALVISO; NASSER DARABIHA

Vitória, ES

Congreso; 16 th Brazilian Congress of Thermal Sciences and Engineering; 2016

ABCM

In 2014, Mario Molina Center performed a study concerning air pollutants in Asunción. The results showed that population of Asunción is exposed to high levels of air pollution particles (ranging between 2.5 and 10 microns) and nitrogen dioxide that threatens their health. In addition, the study showed that transport has an important role inthis problem, due to the fact that emission of particles is one of the main problems of Diesel engines (about 80 % of the total fleet in Paraguay). Most of experimental studies of Diesel fuel combustion are performed using internal combustion engines, in order to characterize the emission and performance of the engine. From the numerical point of view, many studies are performed using homogeneous reactors. However, mainly due to the complexity of its chemical composition,there are only few studies on kinetic modeling of such fuel in a 1D configuration. This paper presents numerical studies of Diesel surrogate combustion in laminar counterflow diffusion flame configuration. The key objective of the study is to understand the flame structure of Diesel fuel and validate the kinetic models used in the simulations. The kineticmodelling for Diesel oxidation in the counterflow diffusion flame was performed using the COUNTERFLOW code within the REGATH package developed at EM2C laboratory (Centrale Supelec, France), that takes into account the detailed kinetic and transport phenomena (heat and mass transfer) through a numerical predictive 1D code. A kinetic model was chosen to carry the simulations. This model consists of 150 species and 759 reactions. A surrogate Diesel fuel composed of n-heptane and toluene was chosen to represent Diesel chemistry. Different equivalence ratios and strain rates of Diesel counterflow diffusion flames were studied. The flames structures were analysed and presented.