A Comprehensive Simulation Approach to Irregular Combustion

Lauer, Thomas; Heiss, Michael; Bobicic, Nikola; Holly, Werner; Pritze, Stefan

doi:10.4271/2014-01-1214

Cited by 24 publications

(11 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Currently, this explanation regarding the ingress of oil into the combustion chamber is widely accepted [72,75]. The release of oil droplets from the piston crevice at the end of the compression stroke has also been observed by Kassai et al [76] Lauer et al [77] confirmed that pre-ignition frequently leads to follow-up events. Their optical results suggested that the first pre-ignition is triggered by oil/fuel droplets while subsequent events are initiated by hot particles.…”

Section: Pre-ignition-sourcessupporting

confidence: 48%

Recent Progress in Automotive Gasoline Direct Injection Engine Technology

Shuai

et al. 2018

Automot. Innov.

View full text Add to dashboard Cite

Gasoline direct injection (GDI) engines are currently the dominant powertrains for passenger cars. With the implementation of increasingly stringent fuel consumption and emission regulations worldwide, GDI engines are facing challenges owing to high particulate matter emissions and a tendency to knock, leading to a change in the research and design (R&D) issues compared with those in the twentieth century. This paper reviews the progress in research regarding GDI engine technologies over the past 20 years, focusing on combustion system configurations, and also highlights common issues in GDI R&D, including preignition and deto-knock, soot formation and PM emissions, injector deposits and gasoline compression ignition (GCI). First, an overview of recent developments in the field as driven by regulations is provided, following which progress in injection and combustion systems is examined. Third, the review addresses the occurrence and mechanism of deto-knock and considers means of suppressing this phenomenon. The fourth section discusses soot formation mechanisms and particulate matter emission characteristics of GDI engines and describes the application of gasoline particulate filter (GPF) after-treatment. The subsequent section summarizes studies regarding injector deposit formation, as well as pioneering research into GCI combustion modes. Finally, a summary and future prospects for GDI engine technologies are provided.

show abstract

Section: Pre-ignition-sourcessupporting

confidence: 48%

Recent Progress in Automotive Gasoline Direct Injection Engine Technology

Shuai

et al. 2018

Automot. Innov.

View full text Add to dashboard Cite

show abstract

“…Furthermore, according to the reaction path analysis in Chemkin, which is different from those of other reactive intermediate radicals like H 2 O 2 or CH 2 O, C 8 KET is more stable during the low temperature process. Lauer et al 32 and Magar et al 33 have also confirmed that C 8 KET is the most reactive stable intermediate radical in the low temperature oxidation process.…”

Section: Resultsmentioning

confidence: 86%

3D simulation study on the influence of lubricant oil droplets on pre-ignition in turbocharged DISI engines

Huang

Zhang

et al. 2017

Proceedings of the Institution of Mechanical Engineers, Part D:

View full text Add to dashboard Cite

A skeletal chemical kinetic model for the simulation of auto-ignition and flame propagation characteristics of primary reference fuel (PRF) was developed. Coupled with this model, 3D simulations were applied to investigate the influence of lubricant oil droplets on pre-ignition in a turbocharged direct-injection spark-ignition (DISI) engine at low-speed high-load operating conditions. First, a simulation study on the influence of a lubricant oil droplet on auto-ignition of gasoline substitute and air mixture was performed in a constant-volume chamber. The results revealed that with an increase of the lubricant oil droplet diameter, the ignition delay time for the air/fuel mixture initially decreased and then increased. The ignition delay time was further shortened with the increase of the temperature of the lubricant oil droplet and the temperature and pressure of the mixture. Moreover, it was found that when n-heptane (n-C7H16) was used as a substitute for the direct evaporation product of the lubricant oil droplet, the shortening of the ignition delay time for the air/fuel mixture caused by lubricant oil evaporation was not enough to initiate pre-ignition. When octyl hydrogen peroxide ketone (C8KET) was chosen as a representative of the accumulated stable reactive radicals, the ignition delay time was significantly shortened and was short enough to trigger pre-ignition. Therefore, pre-ignition may not be induced by the direct evaporation product of an lubricant oil droplet but by the accumulated stable reactive radicals. A simulation study on auto-ignition and flame propagation of the air/fuel mixture with the presence of a lubricant oil droplet was then conducted in a turbocharged DISI engine. The results successfully predicted the auto-ignition of the air/fuel mixture near the lubricant oil droplet before the spark ignition timing. Finally, a more convincing mechanism for pre-ignition induced by lubricant oil droplets is proposed to provide some clues for further investigation.

show abstract

“…Multiple auto-ignitions inside cylinder may be observed during the pre-ignition event. Pre-ignition in SI engines are well reported in literature [17,18,19,20,21,22] and methods to suppress the pre-ignition that may lead to super-knock is also suggested in literature [18]. Origin of pre-ignition inside engines through optical measurements is also reported [19].…”

Section: Introductionmentioning

confidence: 80%

“…When pre-ignition is early, the end gas can explode near TDC resulting in a knock event of greater pressure rise. The most vulnerable part during pre-ignition event is the piston, piston rings and valves that are more prone to damage due to excessive momentary pressure buildup during the pre-ignition event that leads to super-knock [17,18].…”

Section: Introductionmentioning

confidence: 99%

Effect of Timing and Location of Hotspot on Super Knock during Pre-ignition

Ali

Pérez

Vedharaj

et al. 2017

SAE Technical Paper Series

View full text Add to dashboard Cite

Pre-ignition in SI engine is a critical issue that needs addressing as it may lead to super knock event. It is widely accepted that pre-ignition event emanates from hot spot(s) that can be anywhere inside the combustion chamber. The location and timing of hotspot is expected to influence the knock intensity from a pre-ignition event. In this study, we study the effect of location and timing of hot spot inside the combustion chamber using numerical simulations. The simulation is performed using a three-dimensional computational fluid dynamics (CFD) code, CONVERGE™. We simulate 3-D engine geometry coupled with chemistry, turbulence and moving structures (valves, piston). G-equation model for flame tracking coupled with multi-zone model is utilized to capture auto-ignition (knock) and solve gas phase kinetics. A parametric study on the effect of hot spot timing and location inside the combustion chamber is performed. The hot spot timing considered are -180 CAD, -90 CAD and -30 CAD and the locations of the hot spots are in the center and two edges of the piston surfaces. Simulation results for normal combustion cycle are validated against the experimental data. The simulation results show great sensitivity to the hot spot timing, and the influence of local temperature gradient is noted to be significant. In case of early hot spot timing of -180 CAD, the pre-ignition event did not lead to super knock. Nevertheless, at late hot spot timing, super knock was realized. On the other hand, the effect of hot spot location on pre-ignition event depends on the geometry of the combustion chamber.

show abstract

A Comprehensive Simulation Approach to Irregular Combustion

Cited by 24 publications

References 13 publications

Recent Progress in Automotive Gasoline Direct Injection Engine Technology

Recent Progress in Automotive Gasoline Direct Injection Engine Technology

3D simulation study on the influence of lubricant oil droplets on pre-ignition in turbocharged DISI engines

Effect of Timing and Location of Hotspot on Super Knock during Pre-ignition

Contact Info

Product

Resources

About