25th International Conference on Urban Transport and the Environment, Urban Transport 2019; Aveiro; Portugal; 25 June 2019 through 27 June 2019; Code 155807In recent years, the growth of fossil fuel use and greenhouse gases emissions (GHGs) has been
promoted by the population increase and development of the industry sector. Due to the increasing
attention towards the effects of climate changes on quality of life, recent researches on pollutant
formation processes have been developed in different sectors, especially in transportation. The last
emission standards on pollutants impose limits on the dimensions and on the particle number of the
particulate matter emissions, because of the highly dangerous effect on human health. To fight high
concentrations of particulate matter (PM) emissions, a wide number of studies are addressed towards
the definition of the most important parameters in effective production of particulate matter,
especially in spark ignition engines. Physical processes such as mixture formation, engine operating
parameters and fuel chemical properties strongly affect the soot formation in gasoline engines. The
heat transfer process between the piston hot surface and the fuel gasoline during the post-injection
phase is a key aspect of soot emissions for an engine. This paper is devoted to analyzing
the fundamental parameters that are responsible for pollutant formation in the transport sector and the
actual experimental and numerical techniques used to predict the environmental impact of engines
