Refine Your Search

Topic

Author

Affiliation

Search Results

Collection

HCCI, 2015

2015-04-14
Classical HCCI combustion with temperature controlling combustion onset and only a modest effect of fuel injection. Papers describing experiments and test data, simulation results focused on applications, fuel/additive effects, combustion control, and mode change are part of this collection.
Collection

RCCI and Dual-Fuel Low Temperature Combustion, 2015

2015-04-14
Computational modeling and analysis of Reactivity Controlled Compression Ignition (RCCI) combustion. Papers focus on analyzing and improving RCCI combustion using novel injection strategies, combustion chamber designs, and fueling combinations.
Collection

HCCI, 2018

2018-04-03
Classical HCCI combustion with temperature controlling combustion onset and only a modest effect of fuel injection. Papers describing experiments and test data, simulation results focused on applications, fuel/additive effects, combustion control, and mode change are invited are included in this collection.
Collection

HCCI, 2017

2017-03-28
Classical HCCI combustion with temperature controlling combustion onset and only a modest effect of fuel injection. Papers describing experiments and test data, simulation results focused on applications, fuel/additive effects, combustion control, and mode change are invited are included in this collection.
Collection

Advanced Hybrid and Electric Vehicle Powertrains, 2018

2018-04-03
The papers in this collection cover recent advances in research, development and engineering of hybrid, plug-in hybrid, and electric powertrains and architectures with particular emphasis on new and near-production technologies.
Collection

High Efficiency IC Engines Concepts, 2017

2017-03-28
The papers in this collection focuses on technologies such as advanced and partially mixed combustion, cooled EGR boosting, ignition and direct injection technologies, pressure boosting, intelligent combustion, thermal efficiency, fully variable valvetrains, and other new and developing technologies.
Video

High Load HCCI Operation Using Different Valving Strategies in a Naturally-Aspirated Gasoline HCCI Engine

2012-02-16
This session focuses on kinetically controlled combustion. Experimental and simulation studies pertaining to various means of controlling combustion are welcome. Examples are research studies dealing with temperature and composition distribution inside the cylinder and their impact on heat release process. Studies clarifying the role of fuel physical and chemical properties in autoignition are also welcome. Presenter Hanho Yun, General Motors Company
Video

2-Stroke CAI Combustion Operation in a GDI Engine with Poppet Valves

2012-06-18
In order to extend the CAI operation range in 4-stroke mode and maximize the benefit of low fuel consumption and emissions in CAI mode, 2-stroke CAI combustion is revived operating in a GDI engine with poppet valves, where the conventional crankcase scavenging is replaced by boosted scavenging. The CAI combustion is achieved through the inherence of the 2-Stroke operation, which is retaining residual gas. A set of flexible hydraulic valve train was installed on the engine to vary the residual gas fraction under the boosting condition. The effects of spark timing, intake pressure and short-circuiting on 2-stroke CAI combustion and its emissions are investigated and discussed in this paper. Results show the engine could be controlled to achieve CAI operation over a wide range of engine speed and load in the 2-stroke mode because of the flexibility of the electro-hydraulic valvetrain system. Presenter Yan Zhang, Brunel University
Video

Boosted HCCI Combustion Using Low-Octane Gasoline with Fully Premixed and Partially Stratified Charges

2012-06-18
High-load HCCI combustion has recently been demonstrated with conventional gasoline using intake pressure boosting. The key is to control the high combustion heat release rates (HRR) by using combustion timing retard and mixture stratification. However, at naturally aspirated and moderately boosted conditions, these techniques did not work well due to the low autoignition reactivity of conventional gasoline at these conditions. This work studies a low-octane distillate fuel with similar volatility to gasoline, termed Hydrobate, for its potential in HCCI engine combustion at naturally aspirated and low-range boosted conditions. The HCCI combustion with fully premixed and partially stratified charges was examined at intake pressures (Pin) from 100 to 180 kPa and constant intake temperature (60�C) and engine speed (1200 rpm).
Collection

HCCI Combustion Processes Modeling, Experients and Mode Change, 2014

2014-04-01
This technical paper collection covers papers describing experiments and test data, simulation results focused on applications, fuel/additive effects, combustion control, and mode change. Papers with an emphasis on the modeling aspects of combustion are also included.
Collection

Powertrains, Fuels & Lubricants - Kinetically Controlled CI Combustion, 2012

2012-09-18
The 8 technical papers in this collection focus on kinetically controlled combustion. Experimental and simulation studies pertaining to various means of controlling combustion are welcome. Examples are research studies dealing with temperature and composition distribution inside the cylinder and their impact on heat release process. Studies clarifying the role of fuel physical and chemical properties in autoignition are also welcome.
Technical Paper

The Research about Thermal Stratification Effect on Pressure Rise Rate in Supercharged HCCI Engine based on Numerical Analysis

2009-11-03
2009-32-0141
The HCCI engine is a next generation engine, with high efficiency and low emissions. However a rate of pressure rise is a major limitation for high load range. Recently, we are able to reduce the rate of pressure rise using thermal stratification. Nevertheless, this was insufficient to produce high power. Without the higher equivalent ratio, one way to improve the power is to increase the intake boost pressure. It is suggested that the rate of pressure rise is reduced by thermal stratification and the power is increased by boost pressure at the same time. The objective of this work is to understand the characteristics of combustion, knock and emissions for using both thermal stratification and the boost pressure. The calculations are performed by CHEMKIN and modified SENKIN. As a result of increasing the boost pressure, a higher IMEP was attained while the rate of pressure rise increased only slightly in the HCCI with thermal stratification.
Technical Paper

Miniature HCCI Free-Piston Engine Compressor For Orthosis Application

2009-11-03
2009-32-0176
A miniature homogenous charge compression ignition (HCCI) free-piston engine compressor aimed at an ankle-foot orthosis application is described. Analysis of the human ankle shows that a fluid power source in the neighborhood of 10 W is needed. To account for compressor and actuator inefficiencies, the power output at the engine cylinder is designed to be 30 W. A compact engine compressor package has been designed and mathematically modeled. Experiments using existing engine components characterized the leakage model. Through the dynamic simulation of the engine, major parameters of the engine have been specified. Simulations indicate that the HCCI free-piston engine compressor, designed in a prototype package scale of about 80×40×20 mm is a viable compact and efficient fluid power supply. Simulation results demonstrate that the overall efficiency of the engine compressor is expected to be 5.9% and that the package should have a higher energy density than batteries.
Journal Article

A Study of HCCI Combustion using Spectroscopic Techniques and Chemical Kinetic Simulations

2009-11-03
2009-32-0070
This study was conducted to investigate the influence of low-temperature reactions on the Homogeneous Charge Compression Ignition (HCCI) combustion process. Specifically, an investigation was made of the effect of the residual gas condition on low-temperature reactions, autoignition and the subsequent state of combustion following ignition. Light emission and absorption spectroscopic measurements were made in the combustion chamber in order to investigate low-temperature reactions in detail. In addition, chemical kinetic simulations were performed to validate the experimental results and to analyze the elemental reaction process. The results made clear the formation behavior of the chemical species produced during low-temperature HCCI reactions.
Journal Article

Improvement of Natural-gas HCCI Combustion by Internal EGR by Means of Exhaust Valve Re-opening

2009-11-03
2009-32-0079
To control natural-gas HCCI combustion, internal exhaust gas recirculation (EGR) by exhaust valve reopening (EVRO) during the induction stroke was applied to a single-cylinder test engine. The results demonstrate that combustion phasing can be controlled successfully by adjusting the EGR ratio, and so improvement of thermal efficiency and reduction in unburned exhaust emissions are feasible. In addition, the results of the EVRO method were compared to those of intake-valve pilot opening (IVPO) during the exhaust stroke. It was shown that EVRO is more useful than IVPO as a heat-recovery method for HCCI combustion.
Technical Paper

Analysis of the combustion dispersion mechanism in HCCI Engine

2009-11-03
2009-32-0086
Delaying CA50(Crank Angle of 50% Heat Release) of the HCCI engine to expansion stroke can lead to high indicated thermal efficiency as well as the avoidance of knocking. However, this method could induce the problem of cycle variability. In this study, the cycle-to-cycle variation of a HCCI engine fueled with DME was investigated. Experimental parameters of each cycle, such as in-cylinder temperature, pressure and gas flow rate, were recorded by fast response system, and analyzed consequently. Moreover, the interdependency between the combustion and the performance parameters were evaluated.
X