While nuclei particles are found in vehicle emissions in low mass concentration, they are being studied since their number concentration may be high and they may contribute to the surface composition of larger particles and health effects associated with pollution. In this work, we obtain information on where particles emitted by an engine were formed/grown. This is done by comparing the measured particle charge fraction distributions to those calculated with Boltzmann theory for the different temperatures relevant to the combustion chamber, exhaust and sampling systems. We have applied this method to analyze the exhaust of a gasoline direct injection engine. Solid core particles with a size of 1–5 nm may be formed at high temperature in the combustion chamber and semivolatile species condense on their surface as the exhaust cools in the tail pipe, in low dilution conditions. Off-line measurements, using Surface Enhanced Raman Spectroscopy (SERS) show that the sampled particles have SERS spectra with typical D and G bands of disordered amorphous carbon similar to those measured for flame-generated nanoparticles.

Investigating the origin of nuclei particles in GDI engine exhausts

Sementa P;Vaglieco BM;Minutolo P
2012

Abstract

While nuclei particles are found in vehicle emissions in low mass concentration, they are being studied since their number concentration may be high and they may contribute to the surface composition of larger particles and health effects associated with pollution. In this work, we obtain information on where particles emitted by an engine were formed/grown. This is done by comparing the measured particle charge fraction distributions to those calculated with Boltzmann theory for the different temperatures relevant to the combustion chamber, exhaust and sampling systems. We have applied this method to analyze the exhaust of a gasoline direct injection engine. Solid core particles with a size of 1–5 nm may be formed at high temperature in the combustion chamber and semivolatile species condense on their surface as the exhaust cools in the tail pipe, in low dilution conditions. Off-line measurements, using Surface Enhanced Raman Spectroscopy (SERS) show that the sampled particles have SERS spectra with typical D and G bands of disordered amorphous carbon similar to those measured for flame-generated nanoparticles.
2012
Istituto Motori - IM - Sede Napoli
Istituto di Ricerche sulla Combustione - IRC - Sede Napoli
Gasoline direct injection engine
Particle nucleation
Electrical charge
DMA
SERS
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.14243/41936
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? 59
social impact