THE INFLUENCE OF RME ON MASS AND NUMBER CONCENTRATION OF NANO PM IN EXHAUST GASES FROM A DIESEL ENGINE

Abstract

Transport is a major source of the particle pollution (PM). Combustion engine particulate emissions have the potential cause adverse health effects. These effects include cancer and other pulmonary and cardiovascular diseases. A substantial proportion of the number of particles, but not the mass, is ultrafine. For example – one million particles of 100 nanometers size with a unit density of 1 g/cm3 have a mass of approximately 0.0005 g. The paper includes research results of mass and number concentration of nanoPM for 1.9 TDI VW exhaust gases fuelled by standard diesel. The measurements were performed for ambient air and 3 different point of engine work (idle speed, low and high load at 2000 rpm). For nanoPM measurements was used Electrical Low Pressure Impactor ELPI from DECATI, was found, among other things, that the biggest mass concentration was at 0.1-10 Pm of PM diameter but the biggest number concentration was at 0,01 – 0,1 Pm and thus for the size of solid particles of at least an order of magnitude smaller than the mass concentration. The biggest the negative differences in the mass concentration occur in the exhaust gases of the RME fuelled engine (in comparison with diesel fuel) at engine idling when the smallest injection pressure and temperature inside the engine cylinder exist and the oxygen availability is also the lowest (because of the small charging pressure and high EGR rate). Such measurements are important not only in terms of utilitarian but also in cognitive sense – for determining the effect of the engine construction parameters and/or regulating the engine (or the fuel composition) on the mass and the number of nanoparticles emitted in the exhaust gases.