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Standard

Two-Stroke-Cycle Gasoline Engine Lubricants Performance and Service Classification

2003-07-31
CURRENT
J2116_200307
This SAE Standard was prepared by Technical Committee 1, Engine Lubrication, of SAE Fuels and Lubricants Council. The intent is to improve communications among engine manufacturers, engine users, and lubricant marketers in describing lubricant performance characteristics. The key objective is to ensure that a correct lubricant is used in each two-stroke-cycle engine.
Collection

Combustion Control and Optimization, 2014

2014-04-01
This technical paper collection covers engine combustion control and optimization techniques. Topics include engine combustion diagnostics as specialized for control, control methodologies and algorithms, optimization, related combustion sensing, etc.
Collection

Abnormal SI Combustion, 2018

2018-04-03
The papers in this collection focus on abnormal SI combustion processes including spark knock and preignition. Papers cover both 4-stroke and 2-stroke engines characterized by 1) ignition by an external energy source that serves to control combustion phasing, and 2) a combustion rate that is limited by flame propagation.
Collection

Combustion Control and Optimization, 2018

2018-04-03
The papers included in this collection cover engine combustion control and optimization techniques. Topics include engine combustion diagnostics as specialized for control, control methodologies and algorithms, optimization, related combustion sensing, etc.
Collection

Abnormal SI Combustion, 2017

2017-03-28
The papers in this collection focus on abnormal SI combustion processes including spark knock and preignition. Papers cover both 4-stroke and 2-stroke engines characterized by 1) ignition by an external energy source that serves to control combustion phasing, and 2) a combustion rate that is limited by flame propagation.
Technical Paper

Localization of Knock Events in Direct Injection Gasoline Engines

2001-03-05
2001-01-1199
The exploitation of full load capabilities of DI gasoline engines requires at least the same degree of effort as in MPFI engine development. An optics based sensor and sensing technique is presented, which together with conventional pressure indicating provides identification of self ignition centers as the engine is operated under knock or borderline knock conditions. The knock location sensor is configured as a spark plug providing the relevant spark plug properties together with the multichannel optical access into the upper part of the combustion chamber. Functionality and sensitivity of this sensing technique are demonstrated and results for combustion system development are shown.
Technical Paper

Feasibility Study of an Online Gasoline Fractionating System for use in Spark-Ignition Engines

2001-03-05
2001-01-1193
A fuel fractionating system is designed and commissioned to separate standard gasoline fuel into two components by evaporation. The system is installed on a Ricardo E6 single cylinder research engine for testing purposes. Laboratory tests are carried out to determine the Research Octane Number (RON) and Motoring Octane Number (MON) of both fuel fractions. Further tests are carried out to characterize Spark-Ignition (SI) and Controlled Auto-Ignition (CAI) combustion under borderline knock conditions, and these are related to results from some primary reference fuels. SI results indicate that an increase in compression ratio of up to 1.0 may be achieved, along with better charge ignitability if this system is used with a stratified charge combustion regime. CAI results show that the two fuels exhibit similar knock-resistances over a range of operating conditions.
Technical Paper

Wavelet-Based Visualization of Impulsive and Transient Sounds in Stationary Background Noise

2001-04-30
2001-01-1475
Scalograms based on shift-invariant orthonormal wavelet transforms can be used to analyze impulsive and transient sounds in the presence of more stationary sound backgrounds, such as wind noise or drivetrain noise. The visual threshold of detection for impulsive features on the scalogram (signal energy content vs. time and frequency,) is shown to be similar to the audible threshold of detection of the human auditory system for the corresponding impulsive sounds. Two examples of impulsive sounds in a realistic automotive sound background are presented: automotive interior rattle in a vehicle passenger compartment, and spark knock recorded in an engine compartment.
Technical Paper

APIR: A New Firing Concept for the Internal Combustion Engines - sensitivity to knock and in-cylinder aerodynamics

2001-05-07
2001-01-1954
This paper presents a new firing concept for internal combustion engines called APIR and its performances. This concept attempts to merge the best of both Compression Ignition (CI) and Spark Ignition (SI) engine worlds. The application of this concept to a standard SI engine, leads to a consequent improvement of the firing and combustion performances. Initiation and combustion develop with a speed and a repeatability incomparable with the spark plug firing case. The use of the APIR device leads to an increase of the engine operating range in terms of lean operating limit and thus lean burn torque range. This paper points out that the APIR device has a lower knock sensitivity and isn't much affected by the in-cylinder aerodynamics. Thus, it can be shown that to take full advantage of the APIR concept in terms of efficiency and pollutants emissions, the SI engine must be redesigned in terms of compression ratio and in-cylinder aerodynamics.
Technical Paper

PREIGNITION AND SPARK-PLUGS

1920-01-01
200015
The author proposes to determine what features of spark-plug construction cause preignition and how this preignition manifests itself. To this end observed conditions on an Hispano-Suiza aviation engine following 4 hr. of an intended 6-hr. run are reported, with supplementary tests and observations. This resulted in experiments made to determine the cause of preignition, using spark-plugs constructed so that different features of their design were exaggerated. Illustrations of these plugs are shown and the results obtained from their tests are described. The different observed peculiarities are then stated, analyzed and compared with normal spark-plug performance. The experiments serve as a means of identification of special forms of preignition and as an indication of the abnormally high temperatures to which valves and combustion-chamber walls are thus subjected.
Technical Paper

THE VELOCITY OF FLAME PROPAGATION IN ENGINE CYLINDERS

1920-01-01
200010
Flame propagation has received much attention, but few results directly applicable to operating conditions have been obtained. The paper describes a method devised for measuring the rate of flame propagation in gaseous mixtures and some experiments made to coordinate the phenomena with the important factors entering into engine operation; it depends upon the fact that bodies at a high temperature ionize the space about them, the bodies being either inert substances or burning gases. Experiments were made which showed that across a spark-gap in an atmosphere of compressed gas, as in an engine cylinder, a potential difference can be maintained which is just below the breakdown potential in the compressed gas before ignition but which is sufficient to arc the gap after ignition has taken place and the flame has supplied ionization. These experiments and the recording of the results photographically are described.
Technical Paper

Turbocharging a Gasoline Direct Injection Engine

2001-03-05
2001-01-0736
Gasoline direct injection is one of the best way to reduce fuel consumption of spark ignited engines. Stratified combustion has the advantage of drastically increasing the SI engine efficiency. However, whereas future pollution standards become more restricting, it makes after-treatment of NOx emissions more difficult, especially since NOx traps require very low sulfur level in fuel. Thus, engines working with this type of combustion are expensive to be after-treated and actual consumption benefits on the urban cycles are significantly lower than theoretical expectations without any pollution constraint. Homogeneous stoechiometric conditions present lots of advantages. After-treatment can be easily achieved without too expensive systems and applications of this combustion mode on current naturally aspirated engines show high volumetric efficiency and compression ratio in comparison with intake port injection.
Technical Paper

Knock Prediction in Reciprocating Gas-Engines Using Detailed Chemical Kinetics

2001-03-05
2001-01-1012
Two and three-dimensional test cases were simulated using a detailed kinetic mechanism for di-methyl ether to represent methane combustion. A piston-bowl assembly for the compression and expansion strokes with combustion has been simulated at 1500 RPM. A fine grid was used for the 2-D simulations and a rather coarse grid was used for the 3-D calculations together with a k-ε subgrid-scale turbulence model and a partially stirred reactor model with three time scales. Ignition was simulated artificially by increasing the temperature at one point inside the cylinder. The results of these simulations were compared with experimental results. The simulation involved an engine with a homogeneous charge of methane as fuel. Results indicate that pressure fluctuations were captured some time after the ignition started, which indicates knock conditions.
Technical Paper

Prediction of Pre-ignition Reactivity and Ignition Delay for HCCI Using a Reduced Chemical Kinetic Model

2001-03-05
2001-01-1025
Homogeneous Charge Compression Ignition (HCCI) engines have the possibility of low NOx and particulate emissions and high fuel efficiencies. In HCCI the oxidation chemistry determines the auto-ignition timing, the heat release rate, the reaction intermediates, and the ultimate products of combustion. This paper reports an initial effort to apply our reduced chemical kinetic model to HCCI processes. The model was developed to study the pre-ignition characteristics (pre-ignition heat release and start of ignition) of primary reference fuels (PRF) and includes 29 reactions and 20 active species. The only modifications to the model were to make the proscribed adjustments to the fuel specific rate constants, and to enhance the H2O2 decomposition rate to agree with published data.
Technical Paper

Study of Antiknock Performance Under Various Octane Numbers and Compression Ratios in a DISI Engine

2003-05-19
2003-01-1804
This paper presents a study of antiknock performance under various octane numbers and compression ratios in a direct injection spark ignition (DISI) gasoline engine. The relationship between the octane number and engine performance in the DISI engine-the engine torque and the break specific fuel consumption (BSFC)-was investigated in comparison with a multipoint injection (MPI) engine. Due to the improvement in the charging efficiency and the advance of the ignition timing by cooled aspiration, the engine torque of the DISI engine was improved over that of the MPI engine. It was also found that the octane number requirement (ONR) was reduced. In addition, the possibility of engine performance enhancement at high compression ratios was studied. At high compression ratios, the engine torque is reduced due to the heavy knocking when low octane gasoline is used. However, an improvement in the engine torque has been observed with high octane gasoline.
Technical Paper

Water Injection in IC - SI Engines to Control Detonation and to Reduce Pollutant Emissions

2003-05-19
2003-01-1912
In this paper the effects of water injection in the intake pipe of a single-cylinder standard CFR engine are investigated from an experimental viewpoint. Research was carried out at AGIP Petroli and ISAB ERG Refineries of Priolo Gargallo (SR). Tests were performed according to ASTM Research and Motor Method. Water was supplied by a continuous and pulsed injection system. The engine was fed with low Octane Number (O.N.) base gasoline (cheap products, intermediate of refinery processes). The water to fuel mass flow rate ratio was varied in the range 0 to 2. Measurements of O.N. have shown that water injection virtually increases the water/fuel mixture O.N. and that it is possible to obtain a correct run feeding the engine with a low octane number fuel. The pollutant emissions measurements confirm the effectiveness of water injection in reducing the engine environmental impact.
Technical Paper

Effects of Fuel Properties on Premixed Charge Compression Ignition Combustion in a Direct Injection Diesel Engine

2003-05-19
2003-01-1815
Effects of fuel distillation characteristics and cetane number on premixed charge compression ignition (PCCI) combustion were investigated for the purpose of reducing NOx and PM emissions from a direct injection diesel engine. The test engine had a hole type injection nozzle for conventional diesel combustion at high load operation. A low compression ratio and cooled EGR were applied to the test engine in order to reduce the compression temperature for avoiding pre-ignition. The investigation results show that, in the case of ignition control by EGR, a light fuel with lower distillation characteristics had an advantage of reducing smoke at higher loads. This means that high volatility fuel is effective in promoting lean mixture formation of fuel and air during the ignition delay. Moreover, lowering the cetane number was effective in reducing NOx emissions by suppression of combustion temperature.
Technical Paper

New Knock Localization Methodology for SI Engines

2003-03-03
2003-01-1118
A methodology has been developed to determine, for every cycle on which significant knock is detected, the area in which self-ignition occurs. This methodology is based on the exploitation by a dedicated algorithm of a minimum of 4 simultaneous combustion chamber pressure measurements. The algorithm has been first tested on the results of engine knocking simulation, then applied with success on a single-cylinder engine equipped with classical pressure transducers and with an instrumented cylinder head gasket developed for this application. The results obtained with these two kinds of transducers on several engine configurations and tunings are similar. If the timing and intensity of knock events depend on all engine parameters, its location is especially sensitive to such design parameters as fluid motion into the combustion chamber and spark plug position.
Technical Paper

Prediction of the Knock Limit and Viable Operating Range for a Homogeneous-Charge Compression-Ignition (HCCI) Engine

2003-03-03
2003-01-1092
A method is presented for predicting the viable operating range of homogeneous-charge compression-ignition (HCCI) engines. A fundamental criterion for predicting HCCI knock is described and used to predict the minimum air/fuel ratio (and hence maximum torque) available from the engine. The lean (misfire) limit is computed using a modification of the multi-zone method of Aceves et al. [1]. Numerical improvements are described which allow even very complex fuel chemistry to be rapidly modeled on a standard PC. The viable operating range for an HCCI engine burning a primary reference fuel (PRF 95) is predicted and compared with literature experimental data. The new ability to accurately predict the operating range for any given HCCI engine/fuel combination should considerably simplify the tasks of designing a robust engine and identifying suitable fuels for HCCI.
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