Production of soot in high pressure diesel sprays is known to be dependent on combustion chamber temperature and pressure. To a lesser extent, the injector type and injection pressure also influence soot formation. In real engines, separating the individual role of these parameters is difficult as they are closely coupled. Here we present an optically based method to measure both temperature an...

Comparisons between numerical results and experimental data for a homogeneous charge compression ignition (HCCI) engine with optical accessibility are being presented in this paper. The KIVA – 3V program, a general purpose combustion routine, is being enhanced by implementing the optimized Shell model for the ignition process, applying the extended Zeldovich formulation for nitrogen oxide forma...

On the basis of the stochastic reactor model Partially Stirred Plug Flow Reactor (PaSPFR) a model is developed that accounts for soot and NOx formation in the distributed combustion regime. This is done by means of the joint composition probability density function (PDF). The composition vector consists of the species mass fraction in the gas phase, enthalpy, and four moments of the soot partic...

The effect of temperature on soot formation in a laminar propane diffusion flame was investigated. The temperature of the flame on a Parker Wolf hard burner was varied by adjusting the inert nitrogen content in the oxidizer flow. Local soot aggregate properties, such as aggregate diameters and their number densities as well as soot volume fractions were determined using simultaneous laser light...

The role of soot and volatile aerosol in controlling ice particle formation in cirrus clouds is of global importance for climate. In particular, contrail studies may help to better understand the role of various aerosols in ice formation. Recent results suggest that contrails may contribute a large share to the climate impact of aviation. Hence, better knowledge on contrails is needed for devel...

A three-dimensional reacting flow modeling approach is presented for diesel engine studies that can be used for predictions of trends in soot emissions for a wide range of operating conditions. The modeling framework employs skeletal chemistry for n-heptane for ignition and combustion, and links acetylene chemistry to the soot nucleation process. The soot model is based on integration and modif...

We summarize our current research on combustion aerosols. First, sampling devices for the analyses of flame gases are described. The flame gas samples are investigated by mass spectroscopy and by standard aerosol techniques. Time-of-flight mass spectroscopy is well suited to study formation and growth of soot precursor molecules. Fullerenes can also be seen in some mass spectra of flame gases. ...

Direct injection Diesel-style engines emit solid-phase carbonaceous particulate matter (i.e. soot) at levels that negatively impact both climate change and personal health. Although advances in injection technology have increased atomization and mixing of the injected fuel jet, which reduces local equivalence ratios and decreases soot formation, aftertreatment is still required. This in turn ha...

A new Monte Carlo method termed Comb-like frame Monte Carlo is developed to simulate the soot dynamics. Detailed stochastic error analysis is provided. Comb-like frame Monte Carlo is coupled with the gas phase solver Chemkin II to simulate soot formation in a 1-D premixed burner stabilized flame. The simulated soot number density, volume fraction, and particle size distribution all agree well w...