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    <title>Transport Research International Documentation (TRID)</title>
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
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    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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      <title>Transport Research International Documentation (TRID)</title>
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      <title>Experimental Studies of Gasoline Auxiliary Fueled Turbulent Jet Igniter at Different Speeds in Single Cylinder Engine</title>
      <link>https://trid.trb.org/View/1653424</link>
      <description><![CDATA[Turbulent Jet Ignition (TJI) is a pre-chamber ignition system for an otherwise standard gasoline spark ignition engine. TJI works by injecting chemically active turbulent jets to initiate combustion in a premixed fuel/air mixture. The main advantage of TJI is its ability to ignite and burn, completely, very lean fuel/air mixtures in the main chamber charge. This occurs with a very fast burn rate due to the widely distributed ignition sites that consume the main charge rapidly. Rapid combustion of lean mixtures leads to lower exhaust emissions due to more complete combustion at a lower temperature.         For this research, the effectiveness of the Mahle TJI system on combustion stability, lean limit and emissions in a single cylinder spark engine fueled with gasoline at different speeds was investigated. The combustion and heat release process was analyzed and the exhaust emissions were measured. The results show that the effect of the Mahle TJI system on the lean-burn limit and exhaust emissions varied with engine speeds. The lean limit was extended by increasing the engine speed, to ? = 1.71 with 1,200 rpm, followed by ? = 1.69 with 1,000 rpm and then, ? = 1.51 with 800 rpm. NOx emissions were significantly reduced with increased engine speed under stable combustion conditions, because at higher speeds it was possible to increase the lean limit and offer a lower combustion temperature.       ]]></description>
      <pubDate>Wed, 23 Oct 2019 10:41:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/1653424</guid>
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    <item>
      <title>Thermal efficiency of a dual-mode turbulent jet ignition engine under lean and near-stoichiometric operation</title>
      <link>https://trid.trb.org/View/1625535</link>
      <description><![CDATA[Turbulent jet ignition is a combustion technology that can offer higher thermal efficiency compared to the homogeneous spark ignition engines. A potential combustion-related challenge with turbulent jet ignition is the pre-chamber misfiring due to improperly scavenged combustion residuals and maintaining the mixture composition there. Dual-mode turbulent jet ignition is a novel combustion technology developed to address the aforementioned issues. The dual-mode turbulent jet ignition is an engine combustion technology wherein an auxiliary air supply apart from an auxiliary fuel injection is provided into the pre-chamber. This technology can offer enhanced stoichiometry control and combustion stability in the pre-chamber and subsequently combustion control in the main chamber. In this work, engine testing of a single-cylinder dual-mode turbulent jet ignition engine having a compression ratio of 12.0 was completed with liquid gasoline and the indicated thermal efficiency was measured. High-speed pressure recordings were used to compare and analyze different operating conditions. Coefficient of variation in the indicated mean effective pressure and the global air/fuel equivalence ratio values were used to characterize the engine operation. Lean operating conditions for a global air/fuel equivalence ratio of 1.85 showed an indicated efficiency of 46.8% ± 0.5% at 1500 r/min and 6.0 bar indicated mean effective pressure. In addition, the combustion stability of this engine was tested with nitrogen dilution. The nitrogen diluent fraction was controlled by monitoring the intake oxygen fraction. The dual-mode turbulent jet ignition engine of compression ratio 12.0 delivered an indicated efficiency of 46.6% ± 0.5% under near-stoichiometric operation at 1500 r/min and 7.7 bar indicated mean effective pressure with a coefficient of variation in indicated mean effective pressure of less than 2% for all conditions tested.]]></description>
      <pubDate>Tue, 20 Aug 2019 11:44:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/1625535</guid>
    </item>
    <item>
      <title>A control-oriented combustion model for a turbulent jet ignition engine using liquid fuel</title>
      <link>https://trid.trb.org/View/1625394</link>
      <description><![CDATA[A control-oriented engine model is necessary for developing and validating the associated engine control strategies. For engines equipped with the turbulent jet ignition system, the interaction between the pre- and main-combustion chambers should be considered in the control-oriented model for model-based control strategies that optimize the overall thermal efficiency in real-time. Therefore, a two-zone combustion model based on the newly proposed parameter-varying Wiebe function is proposed. Since the engine uses the liquid fuel, a pre-chamber air–fuel mixing and vaporization model are also developed. The model was validated using the experimental data from a single-cylinder turbulent jet ignition engine under different operational conditions, and the simulation results show a good agreement with the experimental data. The relative simulation error of the in-cylinder pressure is less than 8%. For most of the other pressure-related variables, such as indicated mean effective pressure and main-chamber burn duration, the relative errors are within 5%.]]></description>
      <pubDate>Mon, 22 Jul 2019 20:01:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/1625394</guid>
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    <item>
      <title>High Power-Density, High Efficiency, Mechanically Assisted, Turbocharged Direct-Injection Jet-Ignition Engines for Unmanned Aerial Vehicles</title>
      <link>https://trid.trb.org/View/1633882</link>
      <description><![CDATA[More than a decade ago, the author proposed combined use of direct injection (DI) and jet ignition (JI) to produce high efficiency, high power-density, positive-ignition (PI), lean burn stratified, internal combustion engines (ICEs). Adopting this concept, the latest FIA (Fédération Internationale de l’Automobile) F1 engines, which are electrically assisted, turbocharged, directly injected, jet ignited, gasoline engines and work lean stratified in a highly boosted environment, have delivered peak power fuel conversion efficiencies well above 46%, with specific power densities more than 340 kW/liter. The concept, further evolved, is here presented for unmanned aerial vehicle (UAV) applications. Results of simulations for a new DI JI ICE with rotary valve, being super-turbocharged and having gasoline or methanol as working fuel, show the opportunity to achieve even larger power densities, up to 430 kW/liter, while delivering a near-constant torque and, consequently, a nearly linear power curve over a wide range of speeds.]]></description>
      <pubDate>Mon, 08 Jul 2019 17:34:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/1633882</guid>
    </item>
    <item>
      <title>A control-oriented model of turbulent jet ignition combustion in a rapid compression machine</title>
      <link>https://trid.trb.org/View/1481201</link>
      <description><![CDATA[Turbulent jet ignition combustion is a promising concept for achieving high thermal efficiency and low NOx (nitrogen oxides) emissions. A control-oriented turbulent jet ignition combustion model with satisfactory accuracy and low computational effort is usually a necessity for optimizing the turbulent jet ignition combustion system and developing the associated model-based turbulent jet ignition control strategies. This article presents a control-oriented turbulent jet ignition combustion model developed for a rapid compression machine configured for turbulent jet ignition combustion. A one-zone gas exchange model is developed to simulate the gas exchange process in both pre- and main-combustion chambers. The combustion process is modeled by a two-zone combustion model, where the ratio of the burned and unburned gases flowing between the two combustion chambers is variable. To simulate the influence of the turbulent jets on the rate of combustion in the main-combustion chamber, a new parameter-varying Wiebe function is proposed and used for the mass fraction burned calculation in the main-combustion chamber. The developed model is calibrated using the least-squares fitting and optimization procedures. Experimental data sets with different air-to-fuel ratios in both combustion chambers and different pre-combustion chamber orifice areas are used to calibrate and validate the model. The simulation results show good agreement with the experimental data for all the experimental data sets. This indicates that the developed combustion model is accurate for developing and validating turbulent jet ignition combustion control strategies. Future work will extend the rapid compression machine combustion model to engine applications.]]></description>
      <pubDate>Mon, 23 Oct 2017 13:38:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/1481201</guid>
    </item>
    <item>
      <title>JET IGNITION OF AN ULTRA-LEAN MIXTURE</title>
      <link>https://trid.trb.org/View/217558</link>
      <description><![CDATA[A preliminary study was conducted of jets of active radicals used as igniters for lean fuel mixtures. Jets were generated by combustion or electric discharge.  Experiments were performed in a cylindrical steel vessel, 9 centimeters in diameter and 9 centimeters in length, filled initially with air or an ultra-lean methane-air mixture (equivalence ratio of 0.5) at atmospheric pressure and room temperature. Observations were made by streak photography of light emitted by the jets taken with a rotating mirror camera and by schlieren photography, using a submicrosecond spark discharge in air as a point light source.  Gas dynamic properties of jets were primarily governed by their initial velocity, while the particular process by which they were formed had a secondary role.  Jets of radicals invariably appeared as turbulent plumes which were embedded in blast waves headed by hemispherical shock fronts.  Three interesting properties of jet ignition are examined: controllable depth of penetration so that combustion can be started at any desired location within the charge; zonal pre-turbulization enhancing the combustion process; and wide dispersion resulting in multipoint ignition so that combustion is initiated throughout a relatively large segment of the medium rather than in the form of a small, laminar flame kernel as it does in an unconfined spark discharge.]]></description>
      <pubDate>Sat, 31 Aug 1985 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/217558</guid>
    </item>
    <item>
      <title>A COMPARATIVE STUDY OF PLASMA IGNITION SYSTEMS</title>
      <link>https://trid.trb.org/View/195657</link>
      <description><![CDATA[Performance of an array of plasma ignition systems has been studied in a CFR engine.  This included a standard spark plug, an extended spark plug, a surface discharge plug, and two plasma jet ignitors, one with open cavity and the other with cavity provided with a jet forming orifice.  For all the tests the engine was run at a compression ratio of 8:1, a wide open throttle, and minimum for best torque (MBT) ignition timing.  In this way specific information was obtained on ignition delay, duration of the exothermic combustion process, engine efficiency, and pollutant emissions.  The study demonstrated the effect of various ignition systems on engine performance as the lean operating limit is approached.]]></description>
      <pubDate>Fri, 30 Sep 1983 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/195657</guid>
    </item>
    <item>
      <title>TIME RESOLVED MEASUREMENTS OF THE EXHAUST FROM A JET IGNITION PRECHAMBER STRATIFIED CHARGE ENGINE</title>
      <link>https://trid.trb.org/View/50724</link>
      <description><![CDATA[In the jet-ignition prechamber stratified-charge spark-ignition engine, the fuel-air mixture at the time of combustion is non-uniform.  Instantaneous exhaust mass flow rates and emission concentrations from this engine were measured and used to determine the degree to which this charge stratification persists in the products of combustion immediately downstream of the exhaust valve throughout the exhaust process.  In all the cases studied no appreciable variations, during the exhaust process, were detected either in the air-fuel ratio of the exhaust gases as a function of time or in the instantaneous concentrations of CO2,O2 and NOX.  The experimentally obtained instantaneous HC and CO concentrations in the exhaust, however, displayed large fluctuations and were used to study the sources of these two pollutants in this engine.]]></description>
      <pubDate>Tue, 27 Dec 1977 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/50724</guid>
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