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Indexed by:期刊论文

Date of Publication:2010-02-01

Journal:FUEL

Included Journals:SCIE、EI、Scopus

Volume:89

Issue:2

Page Number:392-398

ISSN No.:0016-2361

Key Words:Mixture formation; Third-generation conical spray; High-speed photography; Simulation

Abstract:The purpose of this study is to investigate the mixture formation processes of a third-generation spray (TGCS), an impinging spray that is intended to be applied in mixture preparation for homogeneous charge compression ignition (HCCI) diesel combustion. The spray visualization is performed in a constant-volume vessel by high-speed photography, to investigate the characteristics of the TGCS, and also to provide a validation for numerical models. Then the behaviors of spray and mixture formation process in a constant-volume vessel and diesel in-cylinder conditions were examined numerically by FIRE v8.5 package. Results of the high-speed photography indicated that the TGCS is characterized by a flexible spray tip penetration and circumferential angle, depending on the impinging angle of the TGCS nozzle. Findings of the numerical simulations in a constant-volume vessel under the spray visualization conditions revealed that after the fuel jets had impinged on the guide wall, the TGCS has a much smaller fuel mass fraction compared with a free spray. Furthermore, simulation results under diesel engine conditions demonstrated that for the TGCS, the fuel-air mixture can achieve circumferential homogeneity at 2 degrees CA after the start of injection (ASOI), and form a comparatively homogeneous lean mixture at 20 degrees CA ASOI. (c) 2009 Elsevier Ltd. All rights reserved.