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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>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Research on Hydrogen Flow Rate Measurement for Fuel Consumption Measurement of Heavy-duty FCV (Second Report)</title>
      <link>https://trid.trb.org/View/2535985</link>
      <description><![CDATA[In order to improve the accuracy of hydrogen consumption measurement using a Coriolis flowmeter, the authors conducted chassis dynamometer tests using a fuel cell vehicle. In this report, they used high-pressure hydrogen that is more than 1MPa and a hydrogen flow meter with a pressure adjustment mechanism to improve measurement accuracy. As a result, even in the transient driving cycles such as WLTC and JE05, where past tests showed variations, test results by Coriolis flowmeter were obtained that closely matched the measured values using the gravimetric method, which was determined from the difference in the weight of the gas cylinder before and after the test.]]></description>
      <pubDate>Mon, 14 Apr 2025 09:35:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2535985</guid>
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    <item>
      <title>Comparison of Air Meter Interface Strategies for Engine Management Systems</title>
      <link>https://trid.trb.org/View/1787033</link>
      <description><![CDATA[When an air meter is specified for an engine management system, air meter accuracy is given high priority. Air meter manufacturers characterize the accuracy of their products using laboratory instrumentation to measure the air meter output vs. flow characteristics. Ultimately the air meter is applied to an engine management system in a vehicle. The engine management system must use the information provided by the air meter without the benefit of laboratory instrumentation. Therefore, the entire measurement system must be considered in evaluating the effective accuracy. The most fundamental aspect to consider is the output signal format between the air meter and the engine management system. Two commonly available formats will be investigated: frequency and voltage. This paper develops the equations relating signal resolution and accuracy to such factors as air meter flow curve shape, air flow dynamic range, analog-to-digital converter resolution, frequency range, timer period resolution, and measurement strategy. These equations will allow evaluation of the uncertainty introduced by the measurement system for both voltage-out and frequency-out air meters. Airflow measurement under steady state conditions is examined for both signal formats. Using the equations developed here, one can compare the tradeoffs in measurement accuracy of various air meter interface approaches for specific situations.]]></description>
      <pubDate>Thu, 14 Nov 2024 09:48:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/1787033</guid>
    </item>
    <item>
      <title>District Highway Maintenance Research On-Call Task 2: Evaluation of New Technologies for Tracking the Distribution of Deicing Materials</title>
      <link>https://trid.trb.org/View/2325988</link>
      <description><![CDATA[This report summarizes the results of a research task that was conducted to analyze Ohio DOT’s use of liquid deicing materials and the tracking capabilities of its snowplows’ distribution systems. The objective of the task was to identify areas for improvement in terms of tracking the liquid application rates and provide ideas on how to evaluate new technologies that may improve tracking. To achieve this objective, a comprehensive audit of Ohio’s current state of the practice was conducted. Areas for improvement were identified and constraints were noted. In addition, a nationwide survey was distributed; the survey served as a metric to compare Ohio’s state of the practice as well as providing leads for new technologies to investigate. Then, vendors were solicited for information about liquid tracking systems that could fit into Ohio’s infrastructure and offer the enhancements Ohio was seeking. Brief research was done on each of these new technologies. Lastly, an evaluation matrix was developed so ODOT can continue pursuing these options. The evaluation matrix lists criteria that should be examined as well as specific elements within each criteria. It also proposes ideas on how to practically evaluate or measure each criteria element. ODOT can use the information presented in this report to select new liquid tracking technologies to test within their research program, and continue working towards optimizing their response to winter weather.]]></description>
      <pubDate>Wed, 07 Feb 2024 16:55:28 GMT</pubDate>
      <guid>https://trid.trb.org/View/2325988</guid>
    </item>
    <item>
      <title>Investigation of a GDI injector with an innovative flowmeter for high-pressure transient flows</title>
      <link>https://trid.trb.org/View/2247670</link>
      <description><![CDATA[A new flowmeter for high pressure flows, characterized by intense dynamic events, is presented. The flowmeter algorithm is based on the measurement of two pressure signals along the investigated pipe, and the flowrate is obtained through an ordinary differential equation given by the combination of the continuity and the momentum partial differential equations. This flowmeter has been applied to a GDI injector to monitor the flowrate that enters the injector during an injection event. A 1D numerical model of the GDI injector has been set up and validated, and the numerical outcomes have been used to confirm the consistency of the experimental results obtained from the new flowmeter, for both single and pilot-main injections. The internal dynamics of the injector has also been investigated, using both the 1D numerical tool and the innovative flowmeter. A possible feedback-control strategy has been set up to compensate for any inaccuracy of the injected mass by applying the flowmeter to the hydraulic high-pressure circuit.]]></description>
      <pubDate>Thu, 19 Oct 2023 11:33:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2247670</guid>
    </item>
    <item>
      <title>Development of Fuel Consumption Measurement Method for Fuel Cell Vehicle - Flow Method corresponding to Pressure Pulsation of Hydrogen flow -</title>
      <link>https://trid.trb.org/View/1812796</link>
      <description><![CDATA[Japan Automobile Research Institute (JARI) have developed the flow method as an easy way of measuring hydrogen consumption of fuel cell vehicles (FCVs) in real-time. A 2004 study on fuel consumption of five models of FCVs, measured by thermal flowmeters and based on gravimetric method, exhibited measurement errors within ±1% range for three models, but the errors were as large as -8% for two models that showed significant pulsation in hydrogen consumption flow. Assuming that the pulsation is the cause of errors in the flow method, the authors analyzed influences of pulsation in each flowmeter from two points (frequency and amplitude) and found that pulsation indeed caused flowmeter errors. Expansion chambers (Buffers) and throttle valves (regulators) were confirmed to have an effect in attenuating pulsation. Amplitude of pulsation shrunk to one tenths when such pulsation-reducing instruments were introduced between pulsating FCVs and flowmeters and were put to test. Fuel consumption was then measured using three types of flowmeters: thermal, sonic and differential-pressure. Results showed error reduction to about ±1% in fuel consumption test patterns in Japan and US, successfully improving the flow method. In this test, thermal flowmeters exhibited particularly high accuracy, with very little variation.]]></description>
      <pubDate>Mon, 26 Sep 2022 09:12:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/1812796</guid>
    </item>
    <item>
      <title>Development of the Torque Detected Type Flowmeter Utilizing Lateral Flow Force</title>
      <link>https://trid.trb.org/View/1813973</link>
      <description><![CDATA[A unique flowmeter has been already proposed by the authors. It utilizes the lateral flow force generated on a plate, which is placed in a rectangular flow channel. In the previous works, the test flowmeter was investigated experimentally to clarify the torque versus flow characteristics. Although the results showed good performance in terms of linearity and repeatability, the deviation between the experimental and analytical results occurred on the high flow rate condition. In this report, in order to improve the performance of the proposed flowmeter, the revised configuration of the flowmeter is proposed. Various experimentally investigations are carried out to verify the performance of the proposed flowmeter.]]></description>
      <pubDate>Tue, 30 Aug 2022 09:16:49 GMT</pubDate>
      <guid>https://trid.trb.org/View/1813973</guid>
    </item>
    <item>
      <title>Deviations and Errors Review on Measuring and Calculating Heavy Fuel Oil Consumption and Fuel Stock Onboard Vessels Equipped With Volumetric Fuel Consumption Flowmeters</title>
      <link>https://trid.trb.org/View/1900119</link>
      <description><![CDATA[A common way of measuring heavy fuel oil consumption on board a vessel is to use volumetric fuel flow meters installed at fuel systems inlets for each of the major fuel consumers. At each stage of the fuel processing cycle, certain mass fuel losses or deviations and calculation errors occur that are not counted accurately into fuel consumption figures. The goal of this paper is to identify those fuel mass losses and measuring/calculating errors and perform their quantitative numerical analysis based on actual data. Fuel mass losses defined as deviations identified during the fuel preparation process are evaporation of volatile organic compounds, water drainage, fuel separation, and leakages while errors identified are flow meter accuracy and volumetric/mass flow conversion accuracy. By utilizing statistical analysis of obtained data from engine logbook extracts from three different ships numerical models were generated for each fuel mass loss point. Measuring errors and volumetric/mass conversion errors are numerically analyzed based on actual equipment and models used onboard example vessels. By computational analysis of the obtained models, approximate percentage losses and errors are presented as a fraction of fuel quantity on board or as a fraction of fuel consumed. Those losses and errors present between 0,001% and 5% of fuel stock or fuel consumption figures for each identified loss/error point. This paper presents a contribution for more accurate heavy fuel oil consumption calculation and consequently accurate declaration of remaining fuel stock onboard. It also presents a base for possible further research on the possible influence of fuel grade, fuel water content on the accuracy of consumption calculation.]]></description>
      <pubDate>Thu, 30 Dec 2021 10:14:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/1900119</guid>
    </item>
    <item>
      <title>Study of Application Method of Transient Flowmeter for Model-based A / F Control</title>
      <link>https://trid.trb.org/View/1770720</link>
      <description><![CDATA[Applying the MBD method to engine control development is improving model accuracy. Model-based control using the improved model is expected. In this research, the authors will explain Model-based A/F control design utilizing transient flow meter. In addition, they describe parameter adjustment time reduction by the extended kalman filter.]]></description>
      <pubDate>Thu, 25 Mar 2021 09:29:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/1770720</guid>
    </item>
    <item>
      <title>Benchmark between Bosch and Zeuch method–based flowmeters for the measurement of the fuel injection rate</title>
      <link>https://trid.trb.org/View/1755512</link>
      <description><![CDATA[Bosch and Zeuch method–based flowmeters use the pressure rise triggered by the injection event in a different way in order to characterize the injected flow-rate time history. These typologies of measurement are the most widely applied to evaluate the injection rate of fuel injection systems. The injection rate of a Common Rail electroinjector has been measured with both Bosch and Zeuch method–based flowmeters. The objective has been to perform a benchmark on these two different flow-rate measuring principles. A slight reduction in the rising slope of the injected flow-rate, an anomalous tail at the end of the injection and a time delay in the flow-rate trace have been observed in the case of the Bosch method measurement. A one-dimensional numerical model of the hydraulic circuit of the flowmeter based on the Bosch method has been developed and validated successfully. This model has then been applied to study the cause and effect relationships between the features of the flowmeter hydraulic circuit and the alteration in the measured injected flow-rate pattern. Design keys for the optimization of the Bosch-based flowmeters are provided, even though the investigation has definitely assessed the superior accuracy of Zeuch method–based flowmeters, at least for the examined working conditions.]]></description>
      <pubDate>Mon, 21 Dec 2020 10:06:38 GMT</pubDate>
      <guid>https://trid.trb.org/View/1755512</guid>
    </item>
    <item>
      <title>A New Method for Measuring Fuel Flow in an Individual Injection in Real Time</title>
      <link>https://trid.trb.org/View/1560710</link>
      <description><![CDATA[Knowledge of fuel mass injected in an individual cycle is important for engine performance and modeling. At the moment, such measurements are not possible on engine or in real time. In this article, a new method using Coriolis flow meters (CFMs) and a new, patented, signal processing technique, known as the Prism, are introduced. CFMs are extensively used for flow measurement both in the automotive industry and further afield and, when coupled with the Prism, have the potential to make these challenging high-speed measurements. A rig-based feasibility study was conducted injecting very small quantities of diesel (3 mg) at pressures of up to 1000 bar at simulated engine speeds of up to 4000 rpm. The results show that these small quantities can in principle be measured. The results also reveal a previously unknown behavior of CFMs when measuring very low flow rates at high speed. The study concludes that by combining high-resonant frequency flow tubes with the Prism technology in a new instrument—the fast next-generation Coriolis (fast NGC) flow meter—it will be possible to measure individual injector flow rates on engine in real time.]]></description>
      <pubDate>Wed, 11 Dec 2019 09:31:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/1560710</guid>
    </item>
    <item>
      <title>Measurement of Gas Flow around Intake Valve to Predict State of In-cylinder Gas</title>
      <link>https://trid.trb.org/View/1595048</link>
      <description><![CDATA[To control next generation engine, it is required to predict state of in-cylinder gas. The authors have obtained gas flow rate around intake valve to improve the prediction. High-response laminar flow meter was used to measure transient gas flow. And, the flow rate around intake valve was calculated by the model of laminar flow meter and intake pipe. This paper shows the evaluation of obtained gas flow rate and integrated charging efficiency.]]></description>
      <pubDate>Thu, 23 May 2019 10:23:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/1595048</guid>
    </item>
    <item>
      <title>Development of the Exhaust Gas Flowmeter Using the Laminar Flow Element</title>
      <link>https://trid.trb.org/View/1595043</link>
      <description><![CDATA[The estrangement of the emission measurement of an approval test mode and the real world is a problem, and Portable Emissions Measurement System (PEMS) measurement is proposed. The exhaust gas flow measurement when the low load that is low flow rate and high pulsation is difficult. Therefore, measurement accuracy of PEMS becomes the problem. In this study, the exhaust gas flowmeter using the laminar flow element was developed. It was evaluated influence on flow rate, temperature and pulsation. From the above, ExLFM showed measurement performance applicable to exhaust gas measurement.]]></description>
      <pubDate>Thu, 23 May 2019 10:23:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/1595043</guid>
    </item>
    <item>
      <title>Fast NGC: A New On-Line Technique for Fuel Flow Measurement</title>
      <link>https://trid.trb.org/View/1580336</link>
      <description><![CDATA[Knowledge of fuel mass injected in an individual cycle is important for engine performance and modelling. Currently direct measurements of fuel flow to individual cylinders of an engine are not possible on-engine or in real-time due to a lack of available appropriate measurement techniques. The objective of this work was to undertake real-time Coriolis fuel flow measurement using GDI injectors on a rig observing fuel mass flow rate within individual fuel injections. This paper evaluates the potential of this technology - combining Coriolis Flow Meters (CFMs) with Prism signal processing together known as Fast Next Generation Coriolis (Fast NGC), and serves as a basis for future transitions on-engine applications. A rig-based feasibility study has been undertaken injecting gasoline through a GDI injector at 150 bar in both single shot mode and at a simulated engine speeds of 1788 and 2978 rpm. The results show that these injections can, in principle, be observed. In addition a number of features of the Fast NGC system unique to gasoline are discussed, and the repeatability of the technique is preliminarily assessed. The study concludes that the Fast NGC system has the potential to measure individual injector flow rates on-engine in real-time.       ]]></description>
      <pubDate>Fri, 01 Mar 2019 09:25:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/1580336</guid>
    </item>
    <item>
      <title>Instantaneous Exhaust Gas Flow Rate Measurement by CO₂ Tracer Method Utilizing Heated NDIR Analyzer</title>
      <link>https://trid.trb.org/View/1500024</link>
      <description><![CDATA[Mass emission of gas components from vehicles are generally obtained by Constant Volume Sampling (CVS) method, though this method measures the averaged mass emission over test cycle. Information of instantaneous mass emission is useful for engine control. A flow rate measurement using CO₂ as a tracer can be a method to calculate the instantaneous mass emission. In this study, two wet base CO₂ analyzers using heated NDIR have been applied for this CO₂ tracer method. In the comparison with CVS-SAO method, the wet base CO₂ analyzers showed better results for exhaust flow rate measurement than dry base CO₂ analyzers.定容量希釈排ガスサンプリングシステムにおいて，加熱NDIR計を用いたCO₂>計により希釈前排ガスと希釈後排ガスのCO₂濃度を測定し，瞬時排ガス流量を計測する手法がある．本装置を用いた場合，前処理としての除湿が不要となる．本装置とサンプルガスを除湿する従来法とを比較したときの性能を検証したので報告する．]]></description>
      <pubDate>Mon, 27 Aug 2018 14:05:59 GMT</pubDate>
      <guid>https://trid.trb.org/View/1500024</guid>
    </item>
    <item>
      <title>Real-time Fuel Consumption Measurement Using Raw Exhaust Flow Meter and Zirconia AFR Sensor</title>
      <link>https://trid.trb.org/View/1499976</link>
      <description><![CDATA[The improvement of fuel efficiency is one of the most important issues in the R&D of powertrain systems. This paper describes a new concept for measuring fuel consumption in real-time, “exhaust flow-AFR method”, which utilizing raw exhaust gas flow rate and exhaust air-to-fuel ratio (AFR). An ultrasonic exhaust flow meter which can measure a wide flow range with no pressure loss, and a fast response zirconia sensor which can be installed onto the exhaust pipe directly were adopted. The exhaust flow-AFR method showed a good correlation with the carbon balance method as a reference under some test conditions. The method also showed short rise/down time and the measurement result of “zero” during fuel cutting as expected.排ガスの瞬時燃料消費量を簡便かつ高速応答で計測する手法を提案する．この手法は超音波方式の排ガス流量計と直挿型O<sub>2</sub>センサによる空燃比計測によって実現した．高い応答速度で，配管内同位置の直接計測を行うことにより時間遅れや応答遅れの影響を受けずに計測を行うことができ，従来計測法との高い相関性を確認できた．]]></description>
      <pubDate>Mon, 23 Apr 2018 16:47:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/1499976</guid>
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