Multipulse Ballistic Injection: A Novel Method for Improving Low Temperature Combustion with Early Injection Timings

• Main Authors: Márton Virt, Gergely Granovitter, Máté Zöldy, Ádám Bárdos, Ádám Nyerges
• Format: Article
• Language: English
• Published: MDPI AG 2021-06-01
• Series: Energies
• Subjects: low temperature combustion; multipulse ballistic injection; wall wetting; mixture homogeneity
• Online Access: https://www.mdpi.com/1996-1073/14/13/3727

Nowadays, increasingly stricter regulations on emission reduction are inducing rapid developments in combustion science. Low-temperature combustion (LTC) is an advanced combustion technology that increases an engine’s thermal efficiency and even provides low emissions of nitrogen oxides (NO_x) and particulate matter (PM). The technology often uses early direct injections to achieve sufficient mixture homogeneity. This leads to increasing wall wetting and lower combustion efficiency. This paper introduces the Multipulse ballistic injection (MBI) method to improve combustion with early injection timings. The research was carried out in a four-cylinder medium-duty diesel engine with high-pressure exhaust gas recirculation (HP-EGR). The investigation was divided into two experiments. In the first experiment, MBI was examined without EGR, and in the second, EGR was applied to study its effects. It was found that the MBI strategy decreased wall wetting and increased homogeneity and the indicated mean effective pressure (IMEP) at early injection angles.