Fuel and soot oxidation in diesel-like conditions

Book · Sat Dec 31 04:00:00 EST 1994

OSTI ID:93160

Cavaliere, A ^[1]; Barbella, R; Ciajolo, A; D`Anna, A; Ragucci, R ^[2]

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1. Univ. degli Studi di Napoli Federico II, Napoli (Italy). Dipt. di Ingegneria Chimica
2. CNR, Napoli (Italy). Inst. di Ricerche sulla Combustione

Diesel combustion has been studied under simplified experimental conditions in a nearly quiescent, high-temperature (900 K), high-pressure (4 MPa) environment by means of two-dimensional (2D) laser light scattering techniques and chemical analysis of gaseous and condensable material sampled by a fast-acting valve. Two model fuels, constituted of a simple alkane hydrocarbon (tetradecane (TD)) and an aromatic/aliphatic mixture ({alpha}-methylnaphthalene/tetradecane), have been used in order to study the effect of the fuel specificity on the combustion process. Temporal profiles of the scattering intensity and of the evolution of the oxidation progress evaluated by CO and CO{sub 2} determinations, have shown the same behavior independently on the fuel type and on the sampling location. For both fuels, the combustion proceeds through the formation of CO and subsequent oxidation to CO{sub 2}, which is anticipated with respect to the appearance of a scattering signal due to soot formation and is almost completed in correspondence of the beginning of soot oxidation. The early phase of the latter process takes place in correspondence of the CO depletion when OH radicals become available. The importance of this result consists in the recognition that mechanisms of soot oxidation by an OH attack can realistically occur in diesel engine combustion and that this is the only pathway through which soot oxidation takes place in characteristic timescales comparable to those of its formation.

• OSTI ID: 93160
• Report Number(s): CONF-940711--
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
33 ADVANCED PROPULSION SYSTEMS
CARBON MONOXIDE
COMBUSTION KINETICS
DIESEL ENGINES
DIESEL FUELS
EXPERIMENTAL DATA
FUEL INJECTION SYSTEMS
HYDROXYL RADICALS
OXIDATION
REACTION INTERMEDIATES
SOOT