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    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <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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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Detecting controlled end-gas autoignition for a pilot-ignited methane/hydrogen premixed blend</title>
      <link>https://trid.trb.org/View/2679081</link>
      <description><![CDATA[This paper aims to better understand the onset and intensity of controlled end-gas autoignition (c-EGAI), which can help extend the knock limit of pilot-injection-ignited combustion modes. A set of experiments was designed where the pilot injection pressure (Pᵢₙⱼ), pilot start of injection (SOI) thermodynamic conditions, and premixed equivalence ratio were varied to induce c-EGAI. Common knock detection techniques such as maximum amplitude of pressure oscillation (MAPO), ringing intensity (RI), and signal energy ratio (SER) were found lacking in their ability to adequately characterize c-EGAI, suggesting that the underlying mechanism differs from conventional knock. Short time Fourier Transform (STFT) analysis showed that c-EGAI excited frequencies in the vicinity of the lowest resonant mode, with amplitudes comparable or greater than the diesel pilot ignition. The number and magnitude of the peaks in the fundamental cylinder oscillation modes (found from STFT) was able to correctly quantify the c-EGAI onset and intensity. To substantiate the time-frequency analysis, a kinetic analysis was performed. The kinetic predictions of end gas autoignition had a 1:1 scaling with the c-EGAI onset determined using the STFT.]]></description>
      <pubDate>Tue, 09 Jun 2026 14:43:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2679081</guid>
    </item>
    <item>
      <title>Simulation study on diesel-ignited ammonia/hydrogen mixture fuel combustion on engine combustion and emission performance</title>
      <link>https://trid.trb.org/View/2608105</link>
      <description><![CDATA[This study focuses on a diesel/ammonia/hydrogen premixed engine, which ignites an ammonia/hydrogen mixture introduced through the intake manifold via in-cylinder direct diesel injection. Simulations were conducted to examine the impact of different ammonia/hydrogen mixing ratios on engine performance. The goal was to identify the optimal mixing ratio for this premixed engine to enhance combustion and emission characteristics. The results demonstrated that with a hydrogen mixing ratio of H10, the maximum in-cylinder pressure increased by 5.8% compared to H0, power output decreased by 0.8%, and fuel consumption rate increased by 1.7%. Additionally, ammonia slip decreased by 86.3%, NOₓ emissions increased by 13%, CO emissions increased by 7.4%, N₂O emissions decreased by 79.2%, and CO₂ emissions remained unchanged. Soot emissions were improved, leading to an overall enhancement in engine performance with hydrogen blending. To achieve the carbon neutrality goal of net-zero carbon emissions, a small amount of diesel ignition, combined with ammonia pre-injection in the intake manifold and a 10% hydrogen blend, presents a more effective solution. The findings of this study contribute to the advancement of ammonia fuel in internal combustion engines and provide theoretical guidance for its practical application. Research aimed at optimising in-cylinder combustion processes and controlling emissions enhances our understanding of the impact of alternative fuels on greenhouse gases and harmful emissions, thereby contributing to the reduction of pollutant emissions.]]></description>
      <pubDate>Mon, 15 Dec 2025 10:34:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/2608105</guid>
    </item>
    <item>
      <title>Modelling of auto-ignition to flame propagation transition for Dual-Fuel combustion</title>
      <link>https://trid.trb.org/View/2483281</link>
      <description><![CDATA[Dual-Fuel (DF) combustion engines are a promising alternative to conventional technologies in terms of efficiency and emissions in particular for heavy duty vehicles or marine engines. DF engines involve the injection of a high reactivity pilot spray as a source of ignition for a lean and low reactivity premixed main charge. As a result, auto-ignition (AI) spots emerging from pilot spray generate premixed flame (PF) combustion of the main charge. Nevertheless, transition from AI to PF is not fully understood and thus challenging in terms of modelling. The main goal of this work is to propose a predictive model valid for both AI and PF regime, including transition phenomena, in a Large-Eddy Simulation (LES) context. Firstly, a set of one-dimensional study is conducted. The limitations of two classical approaches for describing auto-ignition (AI), premixed flame (PF) propagation, and regime transitions are identified. The analysis reveals that transition from AI to PF is rather progressive, and starts with hot flame ignition (HFI). Thickened Flame Model (TFM), including detailed resolution of chemistry, and reveals that standard formulation is unable to represent AI, as thickening factor dramatically increases AI delays. A modelling approach involving a thickening factor relaxation time is proposed for LES of DF engines applications, and appears capable of representing transition from AI to PF phenomena in reactivity stratified situations typically encountered in DF applications. The potential of this approach, its accuracy and its limitations are assessed by comparing the model behaviour against 1D reference test cases, and measurements on an optical test bench.]]></description>
      <pubDate>Thu, 13 Feb 2025 15:00:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/2483281</guid>
    </item>
    <item>
      <title>Enhancing the mechanical properties of crumb rubber concrete through polypropylene mixing via a pre-mixing technique</title>
      <link>https://trid.trb.org/View/2481496</link>
      <description><![CDATA[The utilization of waste tires as aggregates in sustainable concrete production has undergone extensive research over the past several years. However, incorporating crumb tires has been discovered to lead to a reduction in the compressive strength of concrete. This paper introduces a novel technique aimed at enhancing bonding conditions and mechanical properties of rubberized concrete (RuC). The approach involves blending a thermoplastic material (such as polypropylene), tire crumb, and cement as a mineral additive, followed by heat treatment of the mixture. This new method for creating a mixture of plastic rubber particles before adding rubber to concrete is called the pre-mixing technique. By adjusting the plastic component, additive composition, or their mixing ratios, the recuperation of strength in RuC can be enhanced. Compression and stress-strain tests demonstrated that the incorporation of these new synthetic compounds improved compressive strength. Furthermore, properties such as toughness index, ultimate strain, and flexural strength were also elevated. Scanning electron microscope (SEM) results depicted an improved bonding condition in the interfacial transition zone (ITZ) between cement paste and the amalgamated rubber-plastic particles, as opposed to non-modified rubber particles. A strength recovery factor was introduced in which a better evaluation of using rubber and modified rubber on the related strength could be done. The study also proposes a mechanical model for the evaluated rubber concretes, exhibiting minimal error. The investigation revealed that replacing 25 % of fine aggregate with pre-mixed rubber particles resulted in a significant 60.4 % increase in compressive strength. The highest compressive strength recovery, at 52 %, was observed when 10 % of fine aggregate was replaced with pre-mixed rubber. Furthermore, the toughness index exhibited a notable improvement of 68 % and 33 % for 15 % and 25 % replacement of fine aggregate with pre-mixed rubber, respectively.]]></description>
      <pubDate>Thu, 02 Jan 2025 10:14:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/2481496</guid>
    </item>
    <item>
      <title>Experimentally investigating the influence of biodiesel blend (Bio20) injection instead of diesel in methanol dual-fuel HCCI engine performance</title>
      <link>https://trid.trb.org/View/2434005</link>
      <description><![CDATA[This paper aims to examine the effect of a biodiesel blend (Bio20) substitute for diesel on methanol dual-fuel HCCI engine performance. In this work, the existing CI engine is modified into a dual-fuel HCCI engine by attaching the carburetor to the inlet manifold for the supply of methanol. Fuel Jet No. 60 in the carburetor was used to provide a predetermined amount of methanol fuel. The mixture of methanol and air is ignited by diesel/Bio20 injection at the end of the compression stroke. Experimental results showed that methanol with diesel increased ignition delay (ID) and reduced NOX. However, HC, smoke opacity and CO emissions increased drastically compared to a conventional diesel engine. Conversely, methanol with Bio20 reduced ID and promoted combustion helping to reduce smoke opacity, HC and CO emissions. In terms of brake thermal efficiency (BTE) Bio20 instead of diesel gave better performance for a methanol dual-fuel HCCI engine.]]></description>
      <pubDate>Thu, 31 Oct 2024 16:20:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/2434005</guid>
    </item>
    <item>
      <title>A study of flame dynamics and structure in premixed turbulent planar NH₃/H₂/air flames</title>
      <link>https://trid.trb.org/View/2326025</link>
      <description><![CDATA[Ammonia (NH₃) has received considerable attention as a near future carbon-free synthetic fuel due to its economic storage/transportation/distribution, and its potential to be thermally decomposed to hydrogen (H₂). To promote the low burning velocity and heat of combustion of ammonia, one viable option is to enrich pure ammonia with hydrogen. In this study, two quasi direct numerical simulations (quasi-DNS) with detailed chemistry and the mixture-averaged transport model are examined to study stoichiometric planar ammonia/hydrogen/air flames under decaying turbulence. The reactants temperature and pressure are set to 298 K and 1 atm, respectively. The initial turbulent Karlovitz number is changed from 4.3 to 16.9, implying that all the test conditions are located within the thin reaction zones combustion regime. The results indicate that the density-weighted flame displacement speed (Sd*), on average, is higher than the unstrained premixed laminar burning velocity (Sₗ⁰) value for both test cases. This suggests that the flame elements propagate faster than their laminar flame counterpart. With increasing the Karlovitz number, the turbulent burning velocity and the wrinkled flame surface area increase by about 35%. Furthermore, the mean flame stretch factor defined as the ratio of the turbulent to the laminar burning velocity divided by the ratio of the wrinkled to the unwrinkled flame surface area is equal to 1.08. This indicates that the local flamelet velocity value, on average, is higher than the unstrained premixed laminar burning velocity. In addition, the results show that the mean value of the local equivalence ratio for the turbulent conditions is higher than its laminar counterpart due to the preferential diffusion of hydrogen and turbulent mixing. Furthermore, the net production rate of hydrogen is shown to be negatively correlated with the flame front curvature suggesting that the local burning rate is intensified in positively curved regions.]]></description>
      <pubDate>Tue, 19 Mar 2024 15:19:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/2326025</guid>
    </item>
    <item>
      <title>A new concept for high efficiency and clean diesel combustion by controlling mixture distribution with dual zone combustion chamber</title>
      <link>https://trid.trb.org/View/2287594</link>
      <description><![CDATA[While various measures are being promoted globally toward carbon-neutrality, internal combustion engines are required to achieve a further improvement in thermal efficiency in order to generate less CO₂. For diesel engines, premixed charge compression ignition (PCI) combustion has been proposed as a combustion method that can achieve high thermal efficiency and clean emissions simultaneously. However, the application of PCI combustion remains limited to the light load range of certain mass-produced engines as it is difficult to control ignition timing and combustion noise. In this study, the authors developed a new combustion concept, Distribution Controlled partially Premixed Compression Ignition (DCPCI), which enables partially premixed combustion in medium load ranges by spatially controlling fuel mixture distribution. With this DCPCI combustion, they aim for highly efficient and clean combustion by suppressing the interference between the burned gas produced by the earlier stage injection and the subsequent spray with the use of a dual-zone combustion chamber and multi-stage injection. The effectiveness of the new combustion concept was validated by Computational Fluid Dynamics (CFD) analyses, and the improvement in thermal efficiency was confirmed by engine experiments.]]></description>
      <pubDate>Fri, 22 Dec 2023 11:19:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2287594</guid>
    </item>
    <item>
      <title>A priori test of perfectly stirred reactor approach to evaluating mean fuel consumption and heat release rates in highly turbulent premixed flames</title>
      <link>https://trid.trb.org/View/2247658</link>
      <description><![CDATA[Unsteady three-dimensional Direct Numerical Simulation (DNS) data obtained earlier by Dave et al. (J Fluid Mech 2020; 884: A46) from a statistically planar and one-dimensional, highly turbulent, moderately lean hydrogen-air flame propagating in a box are processed to perform a priori test of perfectly stirred reactor model. The test aims in particularly at estimating mesh resolution (or filter width within large eddy simulation framework) required to neglect variations in the temperature and mixture composition within a computational cell when evaluating mean (or filtered) fuel consumption and heat release rates. For this purpose, fuel consumption and heat release rates sampled directly from the DNS data and averaged over a cube of width Δ are compared with fuel consumption and heat release rates calculated using the temperature and species concentrations averaged over the same cube. Moreover, turbulent burning velocities computed by integrating the former and latter rates are compared with one another. A ratio of Δ to a laminar flame thickness δₗ is varied from 0.44 to 1.8. The obtained results indicate that the tested simple approach performs reasonably well (poor) if Δ<0.5δₗ (Δ>δₗ, respectively). This result is further supported by directly filtering fuel consumption rate in a laminar premixed flame. The values of the thickness δₗ, calculated using detail chemical mechanisms for different fuels under elevated temperatures and pressures associated with combustion in piston engines, indicate that it is difficult to satisfy the constraint of Δ<0.5δₗ in contemporary unsteady multidimensional numerical simulations of turbulent burning in such engines.]]></description>
      <pubDate>Wed, 18 Oct 2023 17:00:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/2247658</guid>
    </item>
    <item>
      <title>An improved TRF mechanism for a new turbulent premixed combustion model with application to engine combustion CFD</title>
      <link>https://trid.trb.org/View/2226142</link>
      <description><![CDATA[In the present work, an existing TRF (toluene reference fuel) chemical kinetic mechanism has been improved. In the improvement, the existing TRF mechanism was found to have unphysically higher laminar flame speeds at temperatures greater than 750 K which are typical in engine compression-combustion operating conditions. Eight dominant reactions which mainly control the laminar flame speeds under higher temperatures (T > 750 K) have been identified. Based on a recently published power-law laminar flame speed correlation which is able to provide good predictions under a wide range of engine conditions, correct reaction rate constants for the eight high-temperature dominant reactions have been determined for physical laminar flame speeds. The identification and improvement of the eight high-temperature dominant reactions are the first novelty of this work. In order to simulate ethanol and gasoline blends, a latest ethanol sub-mechanism has been implemented into the TRF mechanism. The improved TRF mechanism was validated using available experimental data in the literature. Based on the improved TRF mechanism, a new mechanism library has been generated, which can be used for an improved mechanism-dynamic-selection turbulent premixed combustion model in which turbulent diffusivity is constructed as a function of local turbulence/thermodynamics conditions. The dynamic turbulent diffusivity sub-model is the second novelty of this work. The improved TRF mechanism and its combination with the improved mechanism-dynamic-selection turbulent premixed combustion model were successfully applied to the prediction of combustion and emissions of GTDI (gasoline turbocharged direct injection) engines under both warm-up and transient cold start operating conditions, indicating that the improved models in this work are beneficial for predictive engine combustion CFD (computational fluid dynamics).]]></description>
      <pubDate>Fri, 22 Sep 2023 09:08:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/2226142</guid>
    </item>
    <item>
      <title>Optical characterization of stratified-premixed natural gas direct-injection combustion regimes</title>
      <link>https://trid.trb.org/View/2157307</link>
      <description><![CDATA[Gaseous fuels for heavy-duty internal combustion engines provide inherent advantages for reducing CO₂, particulate matter (PM), and NOₓ emissions. Pilot-ignited direct-injected NG (PIDING) combustion uses a small pilot injection of diesel to ignite a late-cycle main direct injection of NG, resulting in significant reduction of unburned CH₄ emissions relative to port-injected NG. Previous works have identified NG premixing as a critical parameter establishing indicated efficiency and emissions performance. To this end, a recent experimental investigation using a metal engine identified six general regimes of PIDING heat release and emissions behavior arising from variation of NG stratification through control of relative injection timing (RIT) of the NG with respect to the pilot diesel. The objective of the current work is to provide comprehensive description of in-cylinder fuel mixing of direct injected gaseous fuel and its impacts on combustion and pollutant formation processes for stratified PIDING combustion. In-cylinder imaging of OH*-chemiluminescence (OH*-CL) and PM (700 nm), and measurement of local concentration of fuel is considered for 11 different RIT, representing 5 regimes of stratified PIDING combustion (performed with Pᵢₙⱼ = 22.0 MPa and ϕ=0.63). The magnitude and cyclic variability of premixed fuel concentration near the bowl wall provides direct experimental validation of thermodynamic metrics (RITₚᵣₑₘᵢₓ, SOIng,trans, RIT*) that describe the fuel-air mixture state of all 5 regimes of PIDING combustion. The local fuel concentration develops non-monotonically and is a function of RIT. High indicated efficiency and low CH₄ emissions previously observed for stratified-premixed PIDING combustion in previous (non-optical) investigations are due to: (i) very rapid reaction zone growth (>45 m/s) and (ii) more distributed early reaction zones when overlapping pilot and NG injections cause partial pilot quenching. These results connect and extend the findings of previous investigations and guide the future strategic implementation of NG stratification for improved combustion and emissions performance.]]></description>
      <pubDate>Thu, 01 Jun 2023 09:32:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/2157307</guid>
    </item>
    <item>
      <title>Experimental performance and emissions of additively manufactured high-temperature combustion chambers for micro-gas turbines</title>
      <link>https://trid.trb.org/View/2140225</link>
      <description><![CDATA[To date, 59 countries, representing 54% of global greenhouse gas emissions have made pledges for net-zero emissions targets within this century. This will require cleaner and more efficient sources of energy which is driving research into small-scale engines and auxiliary power units for hybrid vehicles and stationary power generation. A suitable candidate for such applications is the micro gas turbine due to its high-power density, reliability and low emissions. Further development of such engines is required though due to their increasing parasitic energy losses relative to net power output as size decreases. Additive manufacturing offers the design freedom to not only increase efficiencies but to also reduce emissions when applied to the various components of micro gas turbines. This article reports the effects of several additive manufacturing (AM) enabled design features for micro gas turbine combustion chambers via experimental testing of full-scale parts. The main objective of the additively manufactured features is the reduction of exhaust emissions by improving the air-fuel mixture distribution and consequently ignition and combustion. Using additive manufacturing a novel conical radial swirl-stabilized tubular combustor with internal vane fuel injection was created as a baseline for the laboratory testing. Several other features, including augmented backside liner cooling surfaces, in-vane lattice structures for fuel mixing and upstream liner fuel injection rings were also generated to further the investigations into additively manufactured features and their effects on fuel mixing. Using multiple combinations of all these features, 10 geometries were generated and tested at a variety of operating conditions. Three inlet temperatures were tested (500°C, 600°C and 700°C) with varying fuel flow rates to investigate their operating limits at a constant inlet pressure of 4?bar absolute. Test results for the full range of equivalence ratios and operating conditions showed that the upstream liner fuel injection designs generated NOₓ, CO and THC emissions on par with the baseline but showed a reduction in the maximum and minimum operating ranges. This design, however, demonstrated the distinct advantage of being able to ignite at full air mass flow; this is not possible with the baseline designs and is also an added benefit to its main use which is the reduction of liner temperature. Overall, the test results underscore that designing combustion chambers for additive manufacturing can provide a myriad of benefits not only for micro gas turbines but also for other applications requiring high efficiency combustion chambers.]]></description>
      <pubDate>Tue, 23 May 2023 10:12:38 GMT</pubDate>
      <guid>https://trid.trb.org/View/2140225</guid>
    </item>
    <item>
      <title>Development of a medium-duty stoichiometric diesel micro-pilot natural gas engine</title>
      <link>https://trid.trb.org/View/2140222</link>
      <description><![CDATA[Fueling a compression-ignition engine with premixed natural gas offers the potential to combine a clean-burning, low-carbon fuel with a high compression ratio, high-efficiency engine. This work describes the development of a multi-cylinder 6.7 L diesel engine converted to run stoichiometric diesel micro-pilot/ natural gas premix combustion with a maximum diesel contribution target of 5% of the total fuel energy and a three-way catalyst aftertreatment system. Results are given by comparing the stoichiometric combustion to the diesel baseline operation, showing combustion characteristics differences, including the rapid two stage heat release. A high load output of 23 bar brake mean effective pressure was obtained with diesel-like brake thermal efficiency of 41%. This operating condition enabled a brake specific CO₂ emissions reduction of up to 25% when compared to diesel. It was observed that the low load output is limited by combustion stability when operated at stoichiometric condition. The three-way catalyst is observed to run at peak efficiency with an equivalence ratio of 1.01. Injector fouling was observed through the inspection of the nozzle and its internal parts, indicating carbon build-up similar to that seen in injector coking mechanisms. A comparison of the developed engine to other engine technologies is given, showing that the diesel micro-pilot natural gas engine performance is in good standing among other diesel and gas engines in the market.]]></description>
      <pubDate>Tue, 23 May 2023 10:12:38 GMT</pubDate>
      <guid>https://trid.trb.org/View/2140222</guid>
    </item>
    <item>
      <title>Multiple fuel injection strategy for premixed charge compression ignition combustion engine using biodiesel blends</title>
      <link>https://trid.trb.org/View/2120665</link>
      <description><![CDATA[In the last decade, advanced combustion techniques of the low-temperature combustion (LTC) family have attracted researchers because of their excellent emission characteristics; however, combustion control remains the main issue for the LTC modes. The objective of this study was to explore premixed charge compression ignition (PCCI) combustion mode using a double pilot injection (DPI; pilot-pilot-main) strategy to achieve superior combustion control and to tackle the soot-oxides of nitrogen (NOₓ) trade-off. Experiments were carried out in a single-cylinder research engine fueled with 20% v/v biodiesel blended with mineral diesel (B20) and 40% v/v biodiesel blended with mineral diesel (B40) vis-à-vis baseline mineral diesel. Engine speed and rate of fuel-mass injected were maintained constant at 1500 rpm and 0.6 kg/h mineral diesel equivalent, respectively. Pilot injection timings (at 45° and 35° before top dead center (bTDC)) and fuel quantities were fixed, while three fuel injection pressures (FIPs) and four different start of the main injection (SoMI) timings were investigated in this study. Results showed that multiple pilot injections resulted in a stable PCCI combustion mode, making it suitable for higher engine loads. For all test fuels, advancing SoMI timings led to relatively lesser knocking; however, engine performance characteristics degraded at advanced SoMI timings. B40 exhibited relatively superior engine performance among different test fuels at lower FIP; however, the difference in engine performance was insignificant at higher FIPs. Fuel injection parameters showed a significant effect on emissions, especially on the NOₓ and particulates. Advancing SoMI timing resulted in 20%–50% lower particulates emissions with a slight NOₓ increase; however, the differences in emissions at different SoMI timings reduced at higher FIPs. Somewhat higher particulates from biodiesel blends were a critical observation of this study, which was more dominant at advanced SoMI timings. Qualitative correlation between NOₓ-total particulate mass (TPM) was another critical analysis, which exhibited the relative importance of different fuel injection parameters for other alternative fuels. Overall, B20 at 700 bar FIP and 20° SoMI timing emerged as the most promising proposition with some penalty in CO emission.]]></description>
      <pubDate>Thu, 23 Mar 2023 10:20:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/2120665</guid>
    </item>
    <item>
      <title>Fuel equivalence ratio and EGR impact on premixed combustion rate and emission output, on a Heavy-Duty Diesel engine</title>
      <link>https://trid.trb.org/View/1805531</link>
      <description><![CDATA[This study aims to show how both NOₓ and soot are affected by EGR dilution when constant, as well as variations in equivalence ratio is applied together with multiple injection strategies. Experiments were conducted in a single cylinder heavy duty research engine. The effects of both EGR and equivalence ratio on partly premixed combustion were investigated. Multiple injections strategies were combined with high EGR levels and lean mixtures. Multiple injections were used to control the combustion phasing and the level of the premixed combustion rate. The diesel combustion conditioning by means of premixed combustion rate, EGR level and oxidant equivalence ratio, leads to low engine emissions. In the load range and configuration tested, emission levels below future emission standards e.g. EURO V have been shown, with no BSFC penalty or exhaust aftertreatment.]]></description>
      <pubDate>Thu, 15 Dec 2022 14:15:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/1805531</guid>
    </item>
    <item>
      <title>An Experimental Study on Characteristics of Premixed Propane Combustion with N₂/CO₂/O₂ Dilution</title>
      <link>https://trid.trb.org/View/2038798</link>
      <description><![CDATA[To reduce pollution and improve thermal efficiency, the characteristics of combustion in internal combustion engines have been investigated for many decades. For different concerns and challenges, research on turbulent combustion was conducted using a constant volume vessel by adding many alternative dilutions. According to previous researches, several essential parameters are discussed that govern combustion performance like Lewis number, Karlovitz number, and so on. However, the mixtures used in these experiments were based on the ratio of 1:3.76 between O₂ and N₂. In this research, the authors focus on the influence of different additions on the combustion performance, which bases on the free ratio between O₂ and N₂, to see whether the parameters still govern the process of combustion or not. By the results of this research, it was found that the combustion performance changes greatly and the governing parameters also shift when the N₂ ratio reduces.]]></description>
      <pubDate>Mon, 28 Nov 2022 10:56:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2038798</guid>
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