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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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    <language>en-us</language>
    <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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    <item>
      <title>Effects of injector configurations on RCCI mode of combustion in a light-duty diesel engine</title>
      <link>https://trid.trb.org/View/2679094</link>
      <description><![CDATA[Reactivity controlled compression ignition (RCCI) is a promising low temperature combustion technique that reduces nitrogen oxides (NOₓ) and soot emissions simultaneously in diesel engines. This experimental study examines the impact of injector configurations on combustion, performance and emissions of a light-duty diesel engine using compressed natural gas (CNG)-diesel RCCI combustion. Injectors with six, seven and eight holes were tested across low load using a single injection strategy and intermediate loads with a double-injections strategy at 1500 and 2800 rpm, with a start of injection (SOI) sweep. The work aims to address key fundamental questions such as (a) how injector configurations affect combustion phasing, engine-out emissions and associated trade-offs, (b) how single and double injection strategies influence above mentioned outcomes; and (c) whether the performance be further improved while preserving the inherent advantage of low NOₓ and soot emissions in the RCCI strategy. The six-hole injector showed higher peak heat release rates at low loads, while the eight-hole injector showed higher peak heat release rates at intermediate loads. The six-hole injector exhibited the shortest ignition delay and advanced combustion phasing, with a longer combustion duration compared to the seven-hole and eight-hole injectors. The eight-hole injector had higher combustion efficiency at low loads but underperformed at intermediate loads. Carbon monoxide and unburned hydrocarbons emissions were higher for the six-hole injector at low loads and for the eight-hole injector at intermediate loads. NOₓ and soot emissions were decreased with increase in injector hole numbers.]]></description>
      <pubDate>Thu, 11 Jun 2026 09:33:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/2679094</guid>
    </item>
    <item>
      <title>Experimental and simulation studies on combustion and emission characteristics of heavy-duty engines with different ammonia/hydrogen mass ratios and equivalence ratios under low load conditions</title>
      <link>https://trid.trb.org/View/2679093</link>
      <description><![CDATA[In long-distance freight transport, where decarbonization targets are difficult to achieve through electrification, the adoption of cleaner fuels is more applicable to heavy-duty engines. This study explores the effects of ammonia–hydrogen mass ratio and equivalence ratio on the combustion and emissions of heavy-duty engines under low-load conditions. The results show that the indicated thermal efficiency of the engine increased and then decreased as the hydrogen mass ratio increased. Between hydrogen mass ratios of 3.5% and 20%, the blended fuels exhibited higher thermal efficiency during rarefied combustion. As the hydrogen mass ratio increases, NOₓ emissions increase and N₂O emissions decrease. As the equivalence ratio increases, NOₓ emissions first increase and then decrease, and N₂O emissions decrease. Under the low-load conditions of heavy-duty engines, considering performance and emissions, it is recommended to choose an equivalence ratio between 0.6 and 0.7, with a hydrogen mass ratio of 7.5%, can achieve an indicated thermal efficiency of 37.3% or higher, with NOₓ emission of less than 21.12 g/kwh and N₂O emission of less than 0.74 g/kwh.]]></description>
      <pubDate>Thu, 11 Jun 2026 09:33:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/2679093</guid>
    </item>
    <item>
      <title>Ducted fuel injection investigation applied in light-duty compression ignition engines</title>
      <link>https://trid.trb.org/View/2679089</link>
      <description><![CDATA[Ducted fuel injection (DFI) is a promising technology that can modify the combustion process in compression ignition engines to mitigate soot formation. By guiding the spray through ducts, air entrainment is enhanced, promoting a more pronounced premixed combustion phase, reducing the diffusion flame, and consequently suppressing soot generation. While previous studies using constant-volume chambers and optical research engines have demonstrated the potential of DFI and the influence of injector geometry on emissions, few have implemented this approach directly in engines due to the substantial modifications required to the cylinder head. This study proposes and evaluates an alternative DFI configuration suitable for light-duty compression ignition engines, implemented without significant modifications to the engine head. Experiments were conducted in a single-cylinder research engine using a sleeve fitted to the injector, aligning the ducts with the nozzle holes. The limited space introduces constraints such as a trade-off between duct length and stand-off distance, and a duct length shorter than the theoretical liquid penetration length. Results show that the configuration with a 3.5 mm stand-off distance achieved up to a 70% reduction in soot emissions compared to the free-spray baseline, while shorter stand-off distances (2.5 and 3.0 mm) were less effective. Although DFI delays ignition, it enhances air entrainment and premixed combustion, ultimately accelerating the combustion process.]]></description>
      <pubDate>Thu, 11 Jun 2026 09:33:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/2679089</guid>
    </item>
    <item>
      <title>Potential of an In-Cylinder Pressure–Based Combustion Control for
     Compression Ignition Aviation Engines Operated with Sustainable Aviation
     Fuels</title>
      <link>https://trid.trb.org/View/2712077</link>
      <description><![CDATA[The aviation industry represents a significant greenhouse gas emitter and aims to                     reduce net CO2 emissions to zero by 2050. The deployment of                     sustainable aviation fuel (SAF), alongside measures such as increasing engine                     efficiency and enhancing ground handling processes, represents a key driver to                     reach this ambitious goal. SAF exhibits significantly different physical and                     chemical properties compared to conventional kerosene. The corresponding fuel                     specification (ASTM D7566 [1]) currently                     only defines fuel parameters relevant for the use in jet engines. To assess the                     suitability of SAF for the use in compression ignition (CI) aviation engines, a                     collaborative project was conducted at TU Wien—Institute of Powertrain and                     Automotive Technology, together with Austro Engine. ASTM D7566-certified fuels                     like Hydrotreated Vegetable Oil (HVO), Fischer–Tropsch–Kerosene (FTK), and                     Alcohol-to-Jet (AtJ) have been investigated on the engine test bench at TU Wien.                     The core contribution of this study is the experimental evaluation of a                     real-time capable in-cylinder pressure–based combustion control strategy that                     enables fuel-flexible and optimized CI engine operation across a wide range of                     SAF while accounting for mechanical constraints such as peak cylinder pressure                     and pressure rise rate. To evaluate the potential of such a control system,                     optimized engine operation was compared to operation with conventional ECU                     (Engine Control Unit) mapping. Furthermore, the influence of such a real-time                     combustion process optimization on critical emissions like NOx or                     soot has been evaluated. Through the implementation of an in-cylinder                     pressure–based combustion control, a considerable fuel-saving potential could be                     demonstrated across the entire fuel range. As combustion phasing is optimized                     toward early crank angle positions, a slight increase in NOx, with a                     corresponding decrease in soot is observed. Additionally, the use of automotive,                     piezoresistive pressure sensors was examined regarding a potential serial                     application. It has been shown that piezoresistive sensors (standard serial                     parts—calibrated for automotive application) are well-suited for determination                     of combustion phasing, while in-cylinder peak pressure and its position can only                     be determined with insufficient accuracy.]]></description>
      <pubDate>Wed, 10 Jun 2026 17:04:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/2712077</guid>
    </item>
    <item>
      <title>Technology Development of Novel Aftertreatment High Pressure Diesel Delivery Unit to Meet Future Emission Regulations for Medium-Heavy Duty Diesel Engines</title>
      <link>https://trid.trb.org/View/2692244</link>
      <description><![CDATA[Future emission regulations (Euro VII, LEV IV, Tier V, China VII, etc.) will impose more stringent requirements both in terms of regulated pollutants emissions and CO₂ for On-Road and Off-Road Diesel applications. The higher regulatory stringency will require more complex Aftertreatment Systems (ATS) architectures. Among the innovative technologies that will be introduced, the Diesel Dosing Unit (DDU) in the exhaust is emerging as one of the enablers for overall compliance. Currently available DDUs work at low pressure (LP) fuel supply around 5 bar and often require a mixer downstream in the exhaust line to ensure the right level of fuel atomization, evaporation and mixing. The usage of high pressure (HP) fuel supply at around 200 bar, together with component design enhancement and dedicated spray targeting generates advantages in terms of CO₂ both during Diesel Particulate Filter (DPF) regeneration and normal modes and on pollutant emissions in regeneration mode. To quantify the advantages, steady state and transient tests were executed on a state of the art 6.6 L Diesel engine where the HP-DDU was assessed in comparison with LP-DDU which was part of the baseline ATS. The comparison between the two technologies was made by installing the HP-DDU in two ATS layouts: nominal mixing length (as baseline) and reduced mixing length. For both HP-DDU ATS layouts, the mixers present in the baseline LP-DDU were removed. During DPF regeneration, both layouts assessed showed benefit in THC (up to 20%), CO (up to 95% at low flow, 50% at medium flow), and BSFC (up to 1.5-2.0%). Additionally, DPF regeneration tests in transient conditions highlighted better temperature control and higher residual O₂ (after fuel oxidation over the DOC), leading to shorter DPF regeneration duration. In normal mode, a reduced back pressure due to the mixer removal resulted in an estimated CO₂ saving up to 10% at rated power. Considering all the measured benefits, the Dumarey developed HP-DDU technology is considered promising for compliance with upcoming CO₂ and emission regulations worldwide.]]></description>
      <pubDate>Sat, 06 Jun 2026 12:01:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/2692244</guid>
    </item>
    <item>
      <title>Heavy Duty Hydrogen Internal Combustion Engine Emissions Development to Achieve Ultra-low NOx</title>
      <link>https://trid.trb.org/View/2692277</link>
      <description><![CDATA[This paper presents the emissions development of a heavy-duty hydrogen internal-combustion engine (H₂ICE) targeting ultra-low NOx with a design goal of 20 mg/hp-hr. The approach integrates advanced thermal management of the engine and aftertreatment, including engine out NOx management through air-fuel ratio controls and an electric heater to accelerate catalyst light-off and sustain activity at low-load/idle conditions. A diesel-derived aftertreatment system (ATS) is selected to maximize practicality and component commonality, and an integrated controls strategy spanning the engine and ATS is implemented to demonstrate ultra-low NOx capability over EPA certification cycles. The paper concludes with considerations for periodic SCR regeneration to ensure emission compliance.]]></description>
      <pubDate>Sat, 06 Jun 2026 12:01:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/2692277</guid>
    </item>
    <item>
      <title>Emission and Combustion Characteristics of a Hydrogen Direct-Injection Spark Ignition Engine Using EGR</title>
      <link>https://trid.trb.org/View/2692286</link>
      <description><![CDATA[This study experimentally investigates the combined effects of exhaust gas recirculation (EGR) and injection timing on the combustion and emission characteristics of a hydrogen direct injection engine. A single-cylinder 395 cc research engine was used, with injection timing varied from 60° to 180° BTDC and EGR rates from 0% to 30%. In-cylinder pressure, apparent heat release rate (AHRR), NOx, and unburned hydrogen concentrations were measured to analyze the influence of mixture formation and dilution on engine performance. Under non-EGR conditions, retarding the injection timing promoted mixture stratification, resulting in faster flame propagation and shorter combustion duration. However, localized high-temperature regions increased NOx formation, while incomplete combustion in lean or rich zones elevated unburned hydrogen emissions. When EGR was introduced, both ignition delay and combustion duration increased due to reduced oxygen concentration and thermal dilution. Nevertheless, the net indicated mean effective pressure (nIMEP) and indicated thermal efficiency (ITE) decreased by less than 1.6% and 1%, respectively, demonstrating that hydrogen’s fast combustion characteristics compensated for the reactivity loss. As the EGR rate increased, the formation of NOx and the emission of unburned hydrogen showed noticeable changes. At 30% EGR, NOx emissions decreased by up to 76% compared to the non-EGR baseline while maintaining stable combustion. However, excessive EGR resulted in increased unburned hydrogen emissions. These findings confirm that, with a properly optimized EGR rate, EGR is a more effective strategy than injection timing control for NOx reduction, achieving significant reduction with minimal efficiency penalty, and providing design insights for practical hydrogen-fueled engines.]]></description>
      <pubDate>Sat, 06 Jun 2026 12:01:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2692286</guid>
    </item>
    <item>
      <title>Overcoming the Carbon Neutrality Bottleneck: Multidimensional
          Innovations and Future Prospects of Carbon Capture, Utilization, and Storage
          (CCUS) Technology</title>
      <link>https://trid.trb.org/View/2706276</link>
      <description><![CDATA[As the global pursuit of carbon neutrality accelerates, carbon capture,                     utilization, and storage (CCUS) technology is emerging as a critical strategic                     pillar for achieving significant emission reductions and facilitating the                     transition to green development. This review systematically summarizes the                     principal technological pathways and recent advances in carbon capture, resource                     utilization, and storage within CCUS systems, with particular attention to                     innovative directions including advanced adsorption and separation materials,                     synergistic catalytic conversion, biological carbon sequestration, and                     mineralization-based storage. By examining representative engineering practices                     and industrialization cases both domestically and internationally, this paper                     summarizes the major challenges currently facing CCUS, including material costs,                     energy consumption, environmental risks, and large-scale deployment. The                     positive impacts of interdisciplinary integration, process system optimization,                     and policy coordination on the commercialization of CCUS are also discussed. The                     review indicates that overcoming bottlenecks in core materials and process                     technologies, improving regulatory frameworks and market mechanisms, and                     establishing clustered industrial ecosystems are essential for CCUS to spearhead                     the forthcoming low-carbon energy and green industrial revolutions. This paper                     envisions future development trends for CCUS technology, highlights its                     multidimensional strategic value for global carbon governance, energy security,                     and the circular economy, and offers theoretical references and cutting-edge                     insights for scientific research, policy formulation, and industrial                     decision-making in related fields.]]></description>
      <pubDate>Tue, 02 Jun 2026 11:09:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/2706276</guid>
    </item>
    <item>
      <title>Analysis on the Technical Path and Engineering Application of Ship
     Carbon Capture</title>
      <link>https://trid.trb.org/View/2706273</link>
      <description><![CDATA[This study focuses on the engineering application and performance evaluation of                     shipboard carbon capture systems. A process combining amine absorption and                     membrane separation was constructed, and the combined process was applied to a                     typical 7000 TEU container ship. After sea trials, the average carbon dioxide                     capture efficiency achieved by the system exceeded 87%, and the power                     consumption was maintained within an acceptable range. The integrated system                     greatly improved the EEXI and CII index levels and verified its economic                     feasibility in the medium and high carbon price scenario. The payback period of                     the investment costs was reduced to five years. After port coordination tests,                     the operability of ship-shore carbon dioxide transfer was verified, which                     promoted future scalability. The engineering layout, energy recovery design, and                     operation data worked together to provide a practical solution for maritime                     decarbonization. This study provides a valuable technical reference for the                     implementation of the International Maritime Organization (IMO) carbon reduction                     strategy, and also lays a solid foundation for subsequent legislation and system                     standardization.]]></description>
      <pubDate>Tue, 02 Jun 2026 11:09:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/2706273</guid>
    </item>
    <item>
      <title>Enhancing the Understanding of a State-of-the-Art Fe/zeolite Selective Catalytic Reduction Catalyst</title>
      <link>https://trid.trb.org/View/2692223</link>
      <description><![CDATA[Fe/zeolite selective catalytic reduction (SCR) catalysts are commercially used for NOx emissions reduction from diesel engines. In comparison to Cu/zeolite, these catalysts are widely reported to form less NO₂ as a byproduct of the SCR reactions. However, Fe/zeolite SCR is less active than Cu/zeolite for low temperature NOx conversion under standard SCR conditions. In this study, a state-of-the-art Fe/zeolite SCR catalyst is probed with a combination of N₂ physisorption, SEM/EDX, reactor-based performance and active site quantification. Measurements investigate the impact of degreening, mild and extreme hydrothermal aging. In a degreened condition, the impact of water vapor on standard and fast SCR and isothermal desorption of NH₃ is assessed. The Fe/zeolite catalyst’s hydrothermal durability is studied following hydrothermal aging at temperatures from 550°C up to 950°C. NH₃ adsorption and temperature programmed desorption (TPD) and NO₂ adsorption and TPD experiments are used to quantify the surface acidity and active Fe sites of the catalysts, respectively. Kinetic analysis of the standard SCR data is conducted to elucidate the mechanisms responsible for SCR activity loss upon hydrothermal aging. The authors believe the results presented herein can support the industry wide efforts to continue to improve diesel emissions control.]]></description>
      <pubDate>Mon, 01 Jun 2026 11:19:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/2692223</guid>
    </item>
    <item>
      <title>CuSCR Catalysts Under H₂-ICE Exhaust Gas Conditions</title>
      <link>https://trid.trb.org/View/2692206</link>
      <description><![CDATA[In the near to mid-term, hydrogen internal combustion engines (H₂-ICE) can be a bridge technology for reducing carbon emissions. A few challenges anticipated under lean-burn H₂-ICE operation are the significant drop in turbo-out temperatures, combined with higher water content, and the possible presence of unburned hydrogen in the exhaust, which could have a potential impact on performance and durability of the downstream exhaust aftertreatment system, particularly oxidation and selective catalytic reduction (SCR) catalysts, as these conditions can suppress low-temperature oxidation activity, perturb Cu-site speciation and redox cycling in SCR catalysts, and exacerbate hydrothermal aging under sustained wet operation. This study examines the impact of excess water and residual hydrogen on Cu-SCR durability, active site chemistry, and stability for the case with and without an upstream oxidation catalyst, through aging tests at 450 °C and 550 °C. Changes in Cu redox cycles were assessed through site quantification using multiple titration techniques to determine the influence of excess H₂O and H₂ on catalyst performance and aging.]]></description>
      <pubDate>Mon, 01 Jun 2026 11:19:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/2692206</guid>
    </item>
    <item>
      <title>A methodological framework for microscale mapping of carbon emissions from daily multimodal travel: Application to the Helsinki Metropolitan Area</title>
      <link>https://trid.trb.org/View/2673417</link>
      <description><![CDATA[Urban transportation is a key challenge for achieving climate neutrality. However, effective intervention is hindered by a lack of granular data to identify spatially heterogeneous emission hotspots, as scalable approaches for jointly estimating private car and public transport (PT) emissions at high resolution remain scarce. This study introduces a hybrid bottom-up framework to address this issue. By integrating mobile phone-based travel demand data, unified multimodal routing and Life Cycle Assessment (LCA) emission factors, daily travel related CO₂ emissions is mapped at high spatial resolution in the Helsinki Metropolitan Area. The results reveal pronounced spatial disparities: while the inner-city core exhibits high emission intensity across all modes, car emissions in the suburban periphery are found to exceed public transport emissions by over 50 times. Inspecting the emission patterns against underlying urban structures, the key findings show that high-emission clusters align with areas of high income and low job density, with the highest total emissions occurring in a suburban zone 10–20 km from the Helsinki city center. The emission estimates were validated against municipal inventories, showing an overall agreement with the annual totals. The presented approach offers a diagnostic tool that can be beneficial for transport planning and policy to target decarbonization interventions and efforts to areas where they have the most impact.]]></description>
      <pubDate>Mon, 01 Jun 2026 09:13:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/2673417</guid>
    </item>
    <item>
      <title>Exhaust Emissions Characteristics and Variability for Pratt and Whitney JT8D-7A Gas Turbine Engines Subjected to Major Overhaul and Repair</title>
      <link>https://trid.trb.org/View/2698479</link>
      <description><![CDATA[Seven Pratt and Whitney Aircraft (PWA) JT8D-7A turbofan engines were tested at Kennedy International Airport, New York, to evaluate exhaust emissions characteristics and data variability after overhaul. The measured data show that the engines tested did not meet the Environmental Protection Agency (EPA) emission standards. A comparison of the measured data, obtained from the seven overhauled engines evaluated under this program, with new engine data obtained from PWA show that there is a great deal of similarity between the two sets of data. Differences shown in this report between new engine and overhauled engine data are due to the quantity of the engines sampled; the new engine data represent a larger sample size. Satisfactory data can be measured by using the test procedures, instrumentation, and equipment defined in this report.]]></description>
      <pubDate>Sat, 30 May 2026 18:30:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2698479</guid>
    </item>
    <item>
      <title>Exhaust Emission Characteristics and Variability for Maintained General Electric CF6-50 Turbofan Engines</title>
      <link>https://trid.trb.org/View/2701091</link>
      <description><![CDATA[Five General Electric (GE) CF6-50 turbofan engines were tested at the GE overhaul facility in Ontario, California, to quantify and determine the variability of the exhaust emission levels. The effects of heavy maintenance on these emission levels were also studied. Only two of the engines tested actually received major maintenance. Consequently, the data collected is limited in quantity. Conclusions, observations, and recommendations are presented based on this limited data base. No correlation of exhaust emission levels and type of maintenance was possible. The exhaust emission levels of carbon monoxide (CO) and oxides of nitrogen (NOx) have been determined; total hydrocarbon (THC) levels are not quantified. The variability of the CO and NOx species is less than five percent; THC variability is almost 30 percent. The engine emissions did not meet the current or proposed federal standards. Ninety percent of the turbine engine exhaust emissions are produced at the idle power mode. The operational parameters for this important (from the standpoint of emission data collection) mode are vague and should be more defined. The type of fuel used for emission testing has a significant effect on the resultant exhaust emission levels.]]></description>
      <pubDate>Sat, 30 May 2026 18:30:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2701091</guid>
    </item>
    <item>
      <title>Environmental Impacts of Micromobility</title>
      <link>https://trid.trb.org/View/2580789</link>
      <description><![CDATA[Globally, the e-scooter/e-bike network has already spread to more than 500 cities, 60 countries, and five continents, with the largest scooter rental companies counting tens of millions of registered trips. However, it is important to evaluate the environmental impact of these micromobility vehicles. Are these transportation options really as eco-friendly as the media and social networks claim? The fact that e-scooters/e-bikes do not emit gases from exhaust pipes does not necessarily mean that they do not create emissions and are completely eco-friendly. The environmental impact of these micromobility modes depends on their lifecycle, including production, distribution, and disposal. More than half of the emissions are generated from the extraction of necessary raw materials and the manufacturing process. Moreover, e-scooters/e-bikes require batteries that contain rare metals and whose production processes are energy-intensive. Shared e-scooter/e-bike services also involve energy-consuming charging and maintenance processes. Furthermore, e-scooters have a short lifespan, and improper disposal can pose environmental risks. E-scooters/e-bikes are frequently thrown into bodies of water, dropped from buildings, set on fire or otherwise damaged. The positive impact on the climate from manufacturing and using e-scooters/e-bikes could become a reality if significant attention is given to recyclable materials and sustainable development. Choosing renewable energy sources and optimizing every step of the service supply chain is also crucial for maintaining an efficient servicing system.]]></description>
      <pubDate>Thu, 28 May 2026 17:09:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/2580789</guid>
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