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    <title>Transport Research International Documentation (TRID)</title>
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    <atom:link href="https://trid.trb.org/Record/RSS?s=PHNlYXJjaD48cGFyYW1zPjxwYXJhbSBuYW1lPSJkYXRlaW4iIHZhbHVlPSJhbGwiIC8+PHBhcmFtIG5hbWU9InN1YmplY3Rsb2dpYyIgdmFsdWU9Im9yIiAvPjxwYXJhbSBuYW1lPSJ0ZXJtc2xvZ2ljIiB2YWx1ZT0ib3IiIC8+PHBhcmFtIG5hbWU9ImxvY2F0aW9uIiB2YWx1ZT0iMCIgLz48L3BhcmFtcz48ZmlsdGVycz48ZmlsdGVyIGZpZWxkPSJpbmRleHRlcm1zIiB2YWx1ZT0iJnF1b3Q7QnVybmluZyByYXRlJnF1b3Q7IiBvcmlnaW5hbF92YWx1ZT0iJnF1b3Q7QnVybmluZyByYXRlJnF1b3Q7IiAvPjwvZmlsdGVycz48cmFuZ2VzIC8+PHNvcnRzPjxzb3J0IGZpZWxkPSJwdWJsaXNoZWQiIG9yZGVyPSJkZXNjIiAvPjwvc29ydHM+PHBlcnNpc3RzPjxwZXJzaXN0IG5hbWU9InJhbmdldHlwZSIgdmFsdWU9InB1Ymxpc2hlZGRhdGUiIC8+PC9wZXJzaXN0cz48L3NlYXJjaD4=" 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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      <title>Workshop on Mathematical Fire Modeling, March 24–27, 1981</title>
      <link>https://trid.trb.org/View/2709351</link>
      <description><![CDATA[Table of Contents: Opening Remarks, Wayne Howell; Aircraft Fire Scenarios, Constantine Sarkos; FAA Modeling Efforts, Thor Eklund; DACFIR Model Workshop, Charles MacArthur; Correlation Work and Flame Spread, James Quintiere; UNDSAFE Code Applied to Aircraft Cabin Fire Modeling, K. T. Yang; Modeling Heat Fluxes for Aircraft, Ronald Alpert; Enclosure Models Applied to Aircraft, Henri Mitler; Thermochemical Modeling of Burning Aircraft Materials, Kumar Ramohalli; Enclosure Fire Dynamics Model for Interior Cabin Fires, Josette Bellan; Appendix A - Agenda; and Appendix B- Attendees.]]></description>
      <pubDate>Mon, 22 Jun 2026 12:22:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/2709351</guid>
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    <item>
      <title>Prediction of the Burning Rates of Charring Polymers</title>
      <link>https://trid.trb.org/View/2696968</link>
      <description><![CDATA[The processes that take place in the condensed phase of a burning polymer play an important role in the overall combustion. Quantitative understanding of these processes is critical for prediction of ignition and growth of fires. During the past decade, a significant effort has been made to develop mathematical models of polymer pyrolysis. In the current study, a model of burning of two widely used charring polymers, bisphenol A polycarbonate and poly (vinyl chloride), was developed and validated. The modeling was performed using a flexible computational framework called ThermaKin, which was developed in the Federal Aviation Administration laboratory. ThermaKin solves time-resolved energy and mass conservation equations describing a one-dimensional material object subjected to external heat. Most of the model parameters were obtained from the results of direct property measurements, which is a key distinguishing aspect of this work. The model was employed to simulate cone calorimetry experiments performed under a broad range of conditions. Possible sources of error in the model parameterization were analyzed. The results of this study demonstrate that a one-dimensional numerical pyrolysis model can be used to predict the outcome of cone calorimetry experiments performed on a charring and intumescing polymer. A simple sub-model based on the properties of graphite and a single adjustable heat transfer parameter provides a reasonable approximation to the carbonaceous char description.]]></description>
      <pubDate>Mon, 25 May 2026 15:32:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/2696968</guid>
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    <item>
      <title>Predicting the Burning Rates of Noncharring Polymers</title>
      <link>https://trid.trb.org/View/2696956</link>
      <description><![CDATA[This study provides a thorough examination of whether a numerical pyrolysis model, which describes transient energy transport and chemical reactions taking place in a one-dimensional object, can be used as a practical tool for prediction and/or extrapolation of the results of fire calorimetry tests. The focus is on non-charring polymers, in particular—poly(methylmethacrylate), high-impact polystyrene, and high-density polyethylene. First, relevant properties of these materials were measured and/or obtained from the literature. Subsequently, the values of these properties were used to simulate gasification and cone calorimetry experiments, which were performed under a broad range of conditions. A comparison with the experimental results indicates that the model gives reasonably good predictions of the mass loss and heat release histories. It also predicts the evolution of temperature inside the material samples.]]></description>
      <pubDate>Mon, 18 May 2026 11:04:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/2696956</guid>
    </item>
    <item>
      <title>Relationship between Mass Burnt Fraction 50% Crank Angle and Low-Frequency Components in Cylinder Pressure</title>
      <link>https://trid.trb.org/View/2494963</link>
      <description><![CDATA[The estimate method of mass combustion fraction 50% crank angle (MBF50%CA) using the amplitude of the 4th order sine component in the cylinder pressure (b₄) has been confirmed. As b₄ is period 90 degrees, the maximum cylinder pressure crank angle (θₚₘₐₓ) of a general gasoline engine exists in the positive calculation section of the sine wave. When θₚₘₐₓ is delayed, b₄ value of calculation section including θₚₘₐₓ of the b₄ calculation process becomes smaller, and b₄ becomes smaller, and MBF50%CA becomes late. From the above, it is possible to estimate MBF50%CA by b₄.]]></description>
      <pubDate>Mon, 03 Mar 2025 17:02:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/2494963</guid>
    </item>
    <item>
      <title>Steelmaking Slag Recycling as Raw Material and Its Effect on Burning Temperature of Portland Cement Clinker Production</title>
      <link>https://trid.trb.org/View/2292543</link>
      <description><![CDATA[The valorization of industrial wastes plays a significant aspect in decreasing the environmental pollution. The discussed study concerns the recovery of steelmaking slag (SS), produced by a local steel plant, to make this by-product a raw material for Portland cement clinker production. A lab study looks at this slag’s influence on the raw meal reaction capacity and technological parameters (temperature and burning time). Two clinkers were tested, the first is representative of Portland cement clinker made in a cement plant, while the second is a clinker made in the authors' laboratory in which SS replaces the pyrites residue used in the first. The raw meals were determined for the second clinker using different lime saturation factors from 0.89 to 0.95, while in the first clinker, lime saturation was 0.89. Chemical and mineralogical analysis and microscopic examination revealed that the usage of SS did not affect the resulting Portland cement clinker. This slag enables a gain of 100°C on the clinkering temperature, usually 1,450°C, and shortens the burning time by 10 min. The main clinker phases (C₃S, C₂S, C₃A and C₄AF) are present, with very few free-CaO, about 0.3%. The results of the physico-mechanical tests showed that adding SS had no impact on the cement’s quality. With a final compressive strength at 28-day of 43.5 MPa, the cement obtained satisfies the requirements for inclusion in Algeria’s CEM I 42.5 strength class.]]></description>
      <pubDate>Fri, 15 Dec 2023 08:45:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/2292543</guid>
    </item>
    <item>
      <title>Estimation Method of Mass Burnt Fraction 50% Crank Angle Using Low Frequency Components Include in Cylinder Pressure</title>
      <link>https://trid.trb.org/View/2259902</link>
      <description><![CDATA[A correlation has been confirmed between the mass burnt fraction 50% crank angle (MBF50%CA) and b₄/IMEP, which is obtained by dividing the amplitude b₄ of the 4th-order sine component in the cylinder pressure by IMEP. Using this method, MBF50%CA was estimated from b₄/IMEP. As a result, the estimated value was close to that calculated from conventional thermal calculations. The method in this paper has advantages such as low impact on accuracy when the number of sampling data per cycle is reduced, and no need for absolute pressure calibration. This method is expected to be used in actual vehicle measurement.]]></description>
      <pubDate>Mon, 30 Oct 2023 13:45:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/2259902</guid>
    </item>
    <item>
      <title>Uncertainty Quantification of Aviation Fuel Burn Performance</title>
      <link>https://trid.trb.org/View/2114988</link>
      <description><![CDATA[Estimating future aircraft fuel burn performance is essential when setting aviation standards and efficiency goals for future commercial aviation. Changes in fuel efficiency may result from aviation technology enhancements and/or adjustments in aviation operations. In order to support effective decision-making, it is important that fuel burn estimates come with an assessment of the associated uncertainties. This report presents a quantitative approach to evaluating the uncertainty of aircraft fuel burn performance and determining which factors in aircraft technologies or design operations cause the greatest variation in the fuel burn performance. The report investigates varying aircraft configurations using a conventional Boeing 737-800 aircraft and an unconventional configuration MIT D8 (Double Bubble) aircraft. The authors also investigate varying aviation technologies with the D8 configuration using current technologies and advanced technologies.]]></description>
      <pubDate>Wed, 15 Feb 2023 15:58:12 GMT</pubDate>
      <guid>https://trid.trb.org/View/2114988</guid>
    </item>
    <item>
      <title>Optimality considerations for propulsive fuselage power savings</title>
      <link>https://trid.trb.org/View/1778495</link>
      <description><![CDATA[The paper discusses optimality constellations for the design of boundary layer ingesting propulsive fuselage concept aircraft under special consideration of different fuselage fan power train options. Therefore, a rigorous methodical approach for the evaluation of the power saving potentials of propulsive fuselage concept aircraft configurations is provided. Analytical formulation for the power-saving coefficient metric is introduced, and, the classic Breguet–Coffin range equation is extended for the analytical assessment of boundary layer ingesting aircraft fuel burn. The analytical formulation is applied to the identification of optimum propulsive fuselage concept power savings together with computational fluid dynamics numerical results of refined and optimised 2D aero-shapings of the bare propulsive fuselage concept configuration, i.e. fuselage body including the aft–fuselage boundary layer ingesting propulsive device, obtained during the European Union-funded DisPURSAL and CENTRELINE projects. A common heuristic for the boundary layer ingesting efficiency factor is derived from the best aero-shaping cases of both projects. Based thereon, propulsive fuselage concept aircraft design optimality is parametrically analysed against variations in fuselage fan power train efficiency, systems weight impact and fuselage-to-overall aircraft drag ratio in cruise. Optimum power split ratios between the fuselage fan and the underwing main fans are identified. The paper introduces and discusses all assumptions necessary in order to apply the presented evaluation approach. This includes an in-depth explanation of the adopted system efficiency definitions and drag/thrust bookkeeping standards.]]></description>
      <pubDate>Fri, 25 Jun 2021 18:38:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/1778495</guid>
    </item>
    <item>
      <title>Quantile Regression–Based Estimation of Dynamic Statistical Contingency Fuel</title>
      <link>https://trid.trb.org/View/1763239</link>
      <description><![CDATA[Reducing fuel consumption is a unifying goal across the aviation industry. One fuel-saving opportunity for airlines is reducing contingency fuel loading by dispatchers. Many airlines' flight planning systems (FPSs) provide recommended contingency fuel for dispatchers in the form of statistical contingency fuel (SCF). However, because of limitations of the current SCF estimation procedure, the application of SCF is limited. In this study, the authors propose to use quantile regression-based machine learning methods to account for fuel burn uncertainties and estimate more reliable SCF values. Utilizing a large fuel burn data set from a major U.S.-based airline, the authors find that the proposed quantile regression method outperforms the airline's FPS. The benefit of applying the improved SCF models is estimated to be in the range $19 million-$65 million in fuel expense savings as well as 132 million-451 million kilograms of carbon dioxide emission reductions per year, with the lower savings being realized even while maintaining the current, extremely low risk of tapping the reserve fuel. The proposed models can also be used to predict benefits from reduced fuel loading enabled by increasing system predictability, for example, with improved air traffic management.]]></description>
      <pubDate>Tue, 23 Mar 2021 11:13:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/1763239</guid>
    </item>
    <item>
      <title>Pool Fire and Fireball Experiments in Support of the US DOE/DOT/TC Crude Oil Characterization Research Study</title>
      <link>https://trid.trb.org/View/1703444</link>
      <description><![CDATA[This report describes an experimental study of physical, chemical, and combustion characteristics of selected North American crude oils, and how these associate with thermal hazard distances resulting from pool fires and fireballs. The emergence of large volumes of tight oils within the North American Transportation system over the last decade coupled with several high-profile train accidents involving crude oils, has raised questions about the role of oil properties in general, and tight oils in particular, in affecting the severity of hazard outcomes in related crude oil fires. The objective of the pool fire experiments is to measure parameters necessary for hazard evaluation, namely, burn rate, surface emissive power, flame height, and heat flux to an engulfed object. To carry out this objective, a series of 2-m diameter indoor and 5-m diameter outdoor experiments were performed. The objective of the fireball experiments is to measure parameters required for hazard evaluation which include fireball maximum diameter, height at maximum diameter, duration, and surface emissive power using 400-gallons of crude oil per test. The crude oil samples used for the experiments were obtained from several U.S. locations, including including “tight” oils from the Bakken region of North Dakota and Permian region of Texas, and a conventionally produced oil from the U.S. Strategic Petroleum Reserve stockpile. These samples spanned a measurable range of vapor pressure (VPCRx(T)) and light ends content representative of U.S. domestic conventional and tight crudes. The results indicate that all the oils tested here have comparable thermal hazard distances and the measured properties are consistent with other alkane-based hydrocarbon liquids. The similarity of pool fire and fireball burn characteristics pertinent to thermal hazard outcomes of the three oils studied indicate that vapor pressure is not a statistically significant factor in affecting these outcomes. Thus, the results from this work do not support creating a distinction for crude oils based on vapor pressure with regards to these combustion events.]]></description>
      <pubDate>Fri, 08 May 2020 15:57:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/1703444</guid>
    </item>
    <item>
      <title>Development of Improved Thermodynamic Model Using Cylinder Blow by and Double-Wiebe Functions for High Speed Diesel Engine</title>
      <link>https://trid.trb.org/View/1560670</link>
      <description><![CDATA[In the present work, a tuned gas dynamics based blow by model was used for prediction of thermodynamic state variables till start of combustion in a high speed diesel engine. The burn rate fraction was determined from experimental pressure trace using Rassweiller-Withrow method. Furthermore, suitable single and double Wiebe parameters, consistent with the experimental combustion behavior were determined statistically. The comparison with experimental heat release and burn rate fraction confirmed the unsuitability of single Wiebe function for diesel combustion. A stochastic zero-dimensional thermodynamic model was used to predict pressure traces for various load/fueling conditions. The results exhibited a sub-15% error margin between predicted and experimental pressure traces across all crank angles and fuelling rates. Finally, the model constants are proposed as a function of non-dimensional fuelling rate.       ]]></description>
      <pubDate>Fri, 13 Sep 2019 09:44:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/1560670</guid>
    </item>
    <item>
      <title>Prediction of burn rate, knocking and cycle-to-cycle variations of binary compressed natural gas substitutes in consideration of reaction kinetics influences</title>
      <link>https://trid.trb.org/View/1625469</link>
      <description><![CDATA[Since zero-dimensional/one-dimensional simulations of natural gas spark-ignition engines use model theories similar to gasoline engines, the impact of changing fuel characteristics needs to be taken into consideration in order to obtain results of higher quality. For this goal, this article proposes some approaches that consider the influence of binary fuel mixtures such as methane with up to 40 mol% of ethane, propane, n-butane or hydrogen on laminar flame speed and knock behavior. To quantify these influences, reaction kinetics calculations are carried out in a wide range of the engine operation conditions. Obtained results are used to update and extend existing sub-models. The model quality is validated by comparing simulation results with measured heat release rates and knock limit. The benefit of the new sub-models is demonstrated by predicting the influence the fuel takes on engine operating limits in terms of knocking and lean misfire limits, the latter being determined using a cycle-to-cycle variation model.]]></description>
      <pubDate>Fri, 16 Aug 2019 15:51:28 GMT</pubDate>
      <guid>https://trid.trb.org/View/1625469</guid>
    </item>
    <item>
      <title>The effects of boost pressure on stratification and burn duration of gasoline homogeneous charge compression ignition combustion</title>
      <link>https://trid.trb.org/View/1606588</link>
      <description><![CDATA[This article investigates the effects of intake pressure (boost) on the pre-ignition stratification and burn duration of homogeneous charge compression ignition combustion. Full cycle computational fluid dynamics simulations are performed with gasoline kinetics. An intake pressure sweep is performed while maintaining the same combustion timing and mean composition. The burn duration reduces with increasing boost, even though intake temperature is reduced to hold combustion timing constant. It is shown that the compositional stratification increases with boost whereas thermal stratification decreases. A quasi-dimensional model is employed to assess the effect of compositional stratification, pressure, mean temperature and isolate the effect of thermal stratification on burn duration. The analysis reveals that reducing charge temperature neutralizes the effect of increased boost on reactivity and the shorter burn durations at higher boost are primarily due to the lower thermal stratification. It is shown that higher pressures do not significantly increase the mixing and the lower thermal stratification is due to lower wall heat losses per unit charge mass. A follow-up set of non-reacting simulations with adiabatic walls corroborate this claim by revealing a constant magnitude of thermal stratification across the boost sweep.]]></description>
      <pubDate>Thu, 27 Jun 2019 14:53:59 GMT</pubDate>
      <guid>https://trid.trb.org/View/1606588</guid>
    </item>
    <item>
      <title>Laminar Burning Velocity of Market Type Gasoline Surrogates as a Performance Indicator in Internal Combustion Engines</title>
      <link>https://trid.trb.org/View/1562019</link>
      <description><![CDATA[The laminar burning velocity is an important parameter in various combustion models for engine simulations. With respect to computational time for computational fluid dynamics (CFD) and full system engine simulations, the calculation of laminar burning velocities using a detailed chemical mechanism can be replaced by incorporation of approximation formulas, based on rate-ratio asymptotics.         In the present study, a work flow is developed to analyze the engine efficiency performance of spark ignition engines with respect to the laminar burning velocity as a fundamental fuel property. Firstly, methane is used as a fuel to assess practicability of the approach. The procedure is subsequently adopted for market type gasoline surrogates, RON95 and RON100. Detailed chemistry calculations are carried out for the three target fuels using existing state of the art mechanisms, the Aramco [Zhou et al., Proc. Combust. Inst., pp. 403-411, 2017] and the ITV RWTH mechanism [Cai et al., Combust. Flame, pp. 1623-1637, 2015]. Subsequently, the asymptotic-based approximation formula by Göttgens et al. [Göttgens et al., Symp. (Intl.) Combust., pp. 129-135, 1992] is employed and fitted based on detailed simulations under engine relevant conditions. In order to compute fundamental engine performance parameters, such as the indicated mean effective pressures (IMEP), the deduced model is embedded in GT-POWER [Gamma Technologies, LCC.,“GT-SUITE”, 2018], an industry standard tool for engine simulations. Significant differences in IMEP can be observed between calculations with the newly incorporated model and the default model for the laminar burning velocity of methane/air mixtures. Higher burning velocities were found to decrease the burn duration. In order to optimize thermal efficiency, the center of combustion must be delayed by shifting spark timing. For gasoline surrogates, differences in IMEP and efficiency between the two flame speed models were found to be less pronounced. This implies that either the GT-POWER inbuilt flame speed model for gasoline is reasonably good or sensitivities to the laminar burning velocity might not be represented well by the code.       ]]></description>
      <pubDate>Tue, 25 Jun 2019 09:57:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/1562019</guid>
    </item>
    <item>
      <title>Modeling laminar burning velocity of gasoline using an energy fraction-based mixing rule approach</title>
      <link>https://trid.trb.org/View/1601115</link>
      <description><![CDATA[To determine an optimum combustion chamber design and engine operating strategies, computational fluid dynamics simulations of direct-injection spark-ignition engines have become an indispensable step in the powertrain development process. The laminar burning velocity of gasoline is known as an essential input parameter for combustion simulations. In this study, a new methodology for modeling the laminar burning velocity of gasoline for direct-injection spark-ignition engine simulations is proposed. Considering the gasoline as a complex mixture of hydrocarbon fuel, three hydrocarbons, iso-octane, n-heptane, and toluene were incorporated as surrogate fuel components to represent gasoline with distinct aromatic laminar flame characteristics compared to alkane. A mixing rule, based on energy fractions, was adopted to consider the compositional variation of gasoline. The laminar burning velocities of iso-octane, n-heptane, and toluene were calculated under wide thermo-chemical conditions in conjunction with detailed chemical reaction kinetics in the premixed flame simulation. Finally, a set of laminar burning velocity model equations was derived by curve-fitting the flame simulation results of each hydrocarbon component in consideration of the effect of temperature, pressure, and diluent. The laminar burning velocity model was validated against the measurement data of gasoline’s laminar burning velocity found in the literature, and was applied to the computational fluid dynamics simulation of a direct-injection spark-ignition engine under the various operating conditions to explore the prediction capability.]]></description>
      <pubDate>Tue, 28 May 2019 16:50:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/1601115</guid>
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