The performance of boosted gasoline engines is limited at high loads by knock, stochastic Low Speed Pre-Ignition, and Megaknock. An investigation has been carried out on the occurrence of abnormal com....
Most studies on knock ignore the stochastic nature of knock and focus on the onset of knock which is determined by chemical kinetics. This paper focuses on knock intensity (KI) which is determined by ....
This work explores the dependence of fuel ignition delay on stochastic pre-ignition (SPI). Findings are based on bulk gas thermodynamic state, where the effects of kinetically controlled bulk gas pre-....
Modern combustion engines must meet increasingly higher requirements concerning emission standards, fuel economy, performance characteristics and comfort. Especially fuel consumption and the related C....
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 in....
The impact of additive and oil chemistry on low speed pre-ignition (LSPI) was evaluated. An additive metals matrix varied the levels of zinc dialkyldithiophosphate (ZDDP), calcium sulfonate, and molyb....
The current trend of downsizing used in gasoline engines, while reducing fuel consumption and CO2 emissions, imposes severe thermal loads inside the combustion chamber. These critical thermodynamic co....
Highly time resolved measurements of cylinder pressure acquired simultaneously from three transducers were used to investigate the nature of knocking combustion and to identify biases that the pressur....
This study investigates the use of a characteristic reaction time as a possible method to speed up automotive knock calculations. In an earlier study of HCCI combustion it was found that for ignition ....
Combustion in modern spark-ignition (SI) engines is increasingly knock-limited with the wide adoption of downsizing and turbocharging technologies. Fuel autoignition conditions are different in these ....
The experimental work was concerned with improving understanding of the competing effects of the latent heat of vaporization and auto-ignition delay times of different ethanol blended fuels during hea....
The causes of engine knock are well understood but it is important to be able to relate these causes to the effects of controllable engine parameters. This study attempts to quantify the effects of a ....
In a Spark-Ignited engine, there will come a point, as load is increased, where the unburned air-fuel mixture undergoes auto-ignition (knock). The onset of knock represents the upper limit of engine o....
Spark-ignition (SI) engine efficiency is typically limited by fuel auto-ignition resistance, which is described in practice by the Research Octane Number (RON) and the Motor Octane Number (MON). The g....
Natural Gas (NG) is an alternative fuel which has attracted a lot of attention recently, in particular in the US due to shale gas availability. The higher hydrogen-to-carbon (H/C) ratio, compared to g....
The potential benefits of water injection on performance and emissions were investigated on a downsized PFI twin-cylinder turbocharged spark ignition engine. Experiments were carried out at high load ....
Cycle-to-cycle variation in combustion phasing and combustion rate cause knock to occur differently in every cycle. This is found to be true even if the end gas thermo-chemical time history is the sam....
The automotive industry has been witnessing a major shift towards downsized boosted direct injection engines due to diminishing petroleum reserves and increasingly stringent emission targets. Boosted ....
