Composition of carbonaceous fine particulate emissions of a flexible fuel DISI engine under high velocity and municipal conditions

Abstract

A study about the chemical composition of carbonaceous fine particulate emissions of flexible fuel direct injection spark ignition engine under high velocity and municipal conditions was conducted with two different gasoline-ethanol blended fuels (E10 and E85). A self-designed engine test cycle simulating high vehicle velocity conditions of up to of 180 km/h was introduced (high velocity driving cycle, HVDC), simulating a possible motorway scenario without speed legislations as allowed in Germany, and compared to a municipal driving cycle (MDC), which is derived from the New European Driving Cycle (NEDC). The fingerprint of polycyclic aromatic hydrocarbons (PAHs) and their alkylated and oxygenated derivatives as well as the concentrations for PM2.5, elemental carbon (EC), organic carbon (OC) and also for the three most abundant PAHs were determined using a modified thermal optical carbon analyser (TOCA) hyphenated to soft resonance-enhanced multi-photon ionisation mass spectrometry (REMPI-TOFMS). Driving under high velocity conditions resulted in a significant increase of concentrations for PM, EC, OC, methyl-phenanthrenes and pyrene. Engine operation on E85 led to a strong decrease for all concentrations for both cycles. A good correlation was found between concentrations obtained by REMPI-TOFMS and TD-GC/MS. Most prominent PAHs were the alkylated series of phenanthrene, pyrene and naphthalene, whereby the abundances decrease with increasing degree of alkylation. The organic composition between HVDC and MDC mainly differed in quantity and to a lower extent in the aromatic pattern. Nevertheless, methyl-phenanthrenes, pyrene and methyl-pyrenes as well as 4H-cyclopenta[def]phenanthrene and benzo[b]naphtho[1,2-d]furan/benzo[b]naphtho[2,3-d]furan and it alkylated series showed a higher abundance in the pattern under high velocity conditions, where alkylated naphthalenes were enhanced in the MDC mode.

A chemical kinetic modeling study of indene pyrolysis

“…C 17 H 12 is is speculated to be benzo-fluorene [65], and its mole fraction increases significantly with the pressure. m/z = 190 is C 15 H 10 , and its molecular structure is proposed to be 4H-cyclopenta[def]phenanthrene in literature [112,113]. ROP analysis shows that its formation consumes less than 0.1% of indenyl.…”

Co-effects of fuel research octane number and ethanol injection ratio on dual-fuel spark-ignition engine

“…In addition, the application of ethanol may lead to the changes in unregulated emissions. 13 A large number of experiments on emissions have shown that when ethanol blended with gasoline, formaldehyde, 14 acetaldehyde 15 and hydrocarbon (HC), 16 emissions were increased, while HC, olefin, aromatic 17 and particular matter emissions 18 were reduced.…”

Single-particle characterization of polycyclic aromatic hydrocarbons in background air in northern Europe

“…Such distributions are known for pyrogenic PAHs from wood and coal combustion (Czech et al, 2018), in agreement with the source information from LDI. Also gasoline engines emit unsubstituted PAHs of a high molecular weight (Miersch et al, 2019); however, particles from engine emissions have a different inorganic composition (Sodeman et al, 2005;Toner et al, 2006;Toner et al, 2008). The PAH spectra of the K-Nit-Sul and the K-Nit-OC class are almost similar.…”