Study of soot formation during the combustion of Diesel, rapeseed methyl ester and their surrogates in turbulent spray flames

► The sooting behaviour of rapeseed methyl ester (RME) has been studied. ► The addition of RME to Diesel reduces the quantities of soot and soot precursors. ► Different RME surrogates (2 alkanes, 1 alkene and 1 ester) have been tested. ► The effects involved in soot reductions have been identified and quantified. ► Biodiesel soot are bigger than Diesel ones but oxidize faster.