Simultaneous negative PLIF and OH* chemiluminescence imaging of the gasexchange and flame jet from a narrow throat pre-chamber King Abdullah Univ. of Science and Tech

Format:

Book

Conference/Event

Author/Creator:

Tang, Qinglong, author.

Contributor:

Ben Houidi, Moez

Cenker, Emre

Chang, Junseok

Echeverri Marquez, Manuel

Hlaing, Ponnya

Johansson, Bengt

Magnotti, Gaetano

Sampath PhD, Ramgopal

Sharma, Priybrat

Conference Name:

SAE Powertrains, Fuels & Lubricants Meeting (2020-09-22 : Krakow, Poland)

Language:

English

Physical Description:

1 online resource cm

Place of Publication:

Warrendale, PA SAE International 2020

Summary:

Pre-chamber combustion (PCC) is a promising engine combustion concept capable of extending the lean limit at part load. The engine experiments in the literature showed that the PCC could achieve higher engine thermal efficiency and much lower NOx emission than the spark-ignition engine. Improved understanding of the detailed flow and combustion physics of PCC is important for optimizing the PCC combustion. In this study, we investigated the gas exchange and flame jet from a narrow throat pre-chamber by only fueling the prechamber with methane in an optical engine. Simultaneous negative acetone planar laser-induced fluorescence (PLIF) imaging and OH* chemiluminescence imaging were applied to visualize the gas jet and flame jet from the pre-chamber, respectively. Results indicate a delay of the pre-chamber gas exchange relative to the built-up of the pressure difference (P) between the pre-chamber and the main chamber. This should be due to the gas inertia and resistance of the pre-chamber nozzle. The gas jet from the pre-chamber can be either continuous or intermittent depending on the P and pressure fluctuation amplitude. Distinct gas jet from the pre-chamber with low speed is witnessed after 15° CA ATDC, which could account for the post-combustion of the PCC engine in the literature. The probability distribution analysis of the PLIF and OH* images presents a much longer penetration length of the gas jet than that of the flame jet. This means that the flame jet resides in an atmosphere of the unburned gas mixture from the PC when it appears in the main-chamber. The flame jet and gas jet show longer penetration length and become more stable with the enriching of the prechamber charge from lean to stoichiometric. However, the overall gas jet characteristics regarding the penetration length and probability distribution become less sensitive to the pre-chamber global excess air ratio (λ) when the PC charge is close to stoichiometry

Notes:

Vendor supplied data

Publisher Number:

2020-01-2080

Access Restriction:

Restricted for use by site license