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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=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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>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Mechanism analysis on nonlinearity of added resistance in short waves due to bow shape and breaking waves</title>
      <link>https://trid.trb.org/View/2513208</link>
      <description><![CDATA[Added resistance in short waves is significant for large ships, as the waves encountered in their typical operating conditions are primarily short waves. This study numerically investigates the nonlinearity of added resistance in short waves due to bow shapes and breaking waves. The numerical wave generation is first validated to ensure the quality of the incident waves. The original and two modified KVLCC2 hulls in short-wave conditions with various wave heights are simulated to illustrate the nonlinearity of added resistance. The present research demonstrates the effect of bow wave diffraction on added resistance through the analysis of high-order resistance components, the corresponding wave surface and the longitudinal pressure contours. Furthermore, the influence of bow breaking waves on the nonlinearity of high-order resistance components is intuitively demonstrated and discussed through the analyses of pressure and bow wave height, incorporating the evolution of wave elevation. It is discovered that the pressure deficit occurring during breaking waves is a critical factor in this process. The present research deepens the understanding of the underlying mechanisms of added resistance in short waves and contributes to improving the empirical prediction formula.]]></description>
      <pubDate>Tue, 25 Feb 2025 11:41:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/2513208</guid>
    </item>
    <item>
      <title>The `Bow-Wave' Effect in Soft Subgrade Beneath High Speed Rail Lines</title>
      <link>https://trid.trb.org/View/2213469</link>
      <description><![CDATA[This paper discusses the critical speed (the `bow-wave' effect) and how it is influenced by soil stiffness. In order to reach the centers of major conurbation, modern high- speed rail lines are increasingly utilizing marginal land avoiding previously built housing areas. This land often has low soil stiffness. The critical speed of waves across such soils can approach the speed of modern high-speed trains. The large deflections caused can increase environmental noise and the track maintenance required and decrease ride quality. This paper discusses how the effect of train speeds can be predicted using computer modeling and an instrumented impact device. The modeling of possible remedies to the problem are discussed. A convolution technique is used to model axles travelling at different speeds and the effects of multiple axles. The resulting displacements are highly dependent on the amount of damping introduced into the system modeled. In-situ testing, laboratory testing and finite element modeling are compared and are shown to provide consistent results. The conclusion is that a powerful analytical tool for the prediction of the `bow-wave' effect has been devised.]]></description>
      <pubDate>Mon, 16 Dec 2024 11:59:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2213469</guid>
    </item>
    <item>
      <title>Observations of Primary Ship Waves at the Margins of a Confined Tidal River</title>
      <link>https://trid.trb.org/View/2397839</link>
      <description><![CDATA[Primary waves produced by large ships in confined waterways can threaten the sustainability and safety of coastal regions near maritime shipping routes, but the present understanding and predictability of primary wave shallow-water characteristics is hindered by a scarcity of available field observations. This study presents hydrodynamic measurements from 296 primary waves observed in 3.5 to 4.4 m mean water depth throughout four deployments on the channel margins of the Savannah River in Georgia, USA. Ship details and tidally varying waterway parameters are paired with pressure and fluid velocity data to investigate relationships between ship characteristics, waterway conditions, and primary wave magnitudes. Findings show that although larger and faster ships tend to produce larger primary waves, there are inconsistencies among the magnitudes of waves generated by similar ship passages. Additionally, depression prediction equations perform well for most observations, but a small group of “atypically-large” primary waves with depressions exceeding 75 cm are consistently underpredicted and require further investigation. Hydrodynamic, waterway, and ship data are made available in the Supplemental Data.]]></description>
      <pubDate>Fri, 26 Jul 2024 10:00:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/2397839</guid>
    </item>
    <item>
      <title>Binocular reconstruction of breaking ship bow waves in circulating water channel</title>
      <link>https://trid.trb.org/View/2354268</link>
      <description><![CDATA[This study conducts an experiment on the bow waves generated by a 1:80 KRISO container ship (KCS) model in a circulating water channel. The Froude numbers (characterized by the length of perpendiculars) reach high conditions of 0.377, 0.424, and 0.471. A binocular imaging system is employed to reconstruct three-dimensional configurations of the bow wave surface. The dynamic characteristics of bow wave fields are investigated by observing the standard deviation and employing the Proper Orthogonal Decomposition (POD) method. The power spectral density function presents a power-law relationship with frequency. A novel technique referred as Stereoscopic Foam Image Velocimetry (SFIV) is developed to extract the instantaneous three-dimensional velocity of the foam in breaking area. The velocity field obtained through SFIV defines the nominal time-averaged velocity and nominal turbulent energy. A correlation mapping from pixel coordinates to world coordinates is established to evaluate the actual physical uncertainty. The results demonstrate the superior spatiotemporal accuracy and resolution of binocular imaging technology in measuring the characteristics of bow waves. This research provides significant experimental data of surface three-dimensional configurations for the bow waves breaking issues at high Froude numbers.]]></description>
      <pubDate>Fri, 29 Mar 2024 10:16:38 GMT</pubDate>
      <guid>https://trid.trb.org/View/2354268</guid>
    </item>
    <item>
      <title>An experimental study on added resistance focused on the effects of bow wave breaking and relative wave measurements</title>
      <link>https://trid.trb.org/View/1981593</link>
      <description><![CDATA[The added resistance is a resistance component that is not yet satisfactorily predicted, although its accurate estimation is crucial – both from an environmental and economic point of view – from the design stage of a ship until its operation. One of the possible sources of overprediction is the occurrence of bow wave breaking. The first aim of this paper is to study the effect of bow wave breaking on added resistance by combining visual observations with resistance tests. On the other hand, as the bow region of a ship appears to be the most dominant contributor to added resistance, this paper introduces a dynamic waterline detection method involving stereo vision. This experimental method is applied to reach the second aim of this paper, which is to stress the importance of the relative wave elevation in the bow region of the ship. By placing stereo rigs inside the hull of a semi-transparent ship, the waterline at each moment in time can be tracked using an edge detection algorithm. By performing resistance tests on the Delft Systematic Deadrise Series ship model no. 523, the added resistance is observed to be proportional to the relative wave height squared. The data of the experiment and the information necessary to reproduce the experiment are shared through https://doi.org/10.4121/19525852.]]></description>
      <pubDate>Tue, 21 Jun 2022 10:28:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/1981593</guid>
    </item>
    <item>
      <title>Evaluation of bow foils on ship delivered power in waves using model tests</title>
      <link>https://trid.trb.org/View/1940691</link>
      <description><![CDATA[Bow foils have the potential to significantly reduce engine load and CO2 emissions of ships operating in waves. This paper presents the methodology and results of an improved free running experiment for the evaluation of bow foils. The model tests directly measured the change in ship delivered power in waves with and without a bow foil. The results show that the bow foil reduces the delivered power in regular head waves by up to 50% and 12% in irregular waves. In addition to quantifying the comparative contribution due to foil thrust and reduced ship motions in waves, the experiment measured the wave phasing and feathering parameters. The presented dataset, analysis and experimental procedures, which can be used for numerical validation and performance predictions in a range of conditions, demonstrates the potential of energy saving bow foils to reduce engine load and ship emissions.]]></description>
      <pubDate>Wed, 01 Jun 2022 09:19:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/1940691</guid>
    </item>
    <item>
      <title>Resistance and Seakeeping Performance Analysis of an Icebreaker Vessel in Oblique Bow Waves Using SNUFOAM</title>
      <link>https://trid.trb.org/View/1722755</link>
      <description><![CDATA[The present study is concerned with computational fluid dynamics (CFD) analysis of resistance and seakeeping performance of an icebreaker vessel. SNUFOAM, a CFD code developed by Seoul National University towing tank laboratory and specialized in fluid dynamics problem in naval architecture and ocean engineering, was used for this study. In SNUFOAM, the dynamic interface compression method was applied to obtain precise and sharp free-surface behavior. A mesh deforming technique was used to enable six degrees-of-freedom motion. Resistance performance in calm water were analyzed first. By comparison with experimental data, it was confirmed that SNUFOAM accurately predicts the ship resistance. Using SNUFOAM, an analysis procedure on seakeeping performance in regular wave was established and applied to oblique bow wave conditions, to acquire the resistance and motion responses. Test conditions were selected based on Arctic Ocean condition. It was found that the icebreaker vessel satisfies required resistance and seakeeping performance at the design speed.]]></description>
      <pubDate>Wed, 22 Jul 2020 15:52:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/1722755</guid>
    </item>
    <item>
      <title>Field Measurements in the Kiel Canal, Germany: Ship Waves, Drawdown, and Sediment Transport</title>
      <link>https://trid.trb.org/View/1703366</link>
      <description><![CDATA[Ship waves and ship-induced flows are the main hydrodynamic loads on waterway beds and embankments. However, the underlying physical processes are not yet understood fully. Recent field measurements, conducted in the Kiel Canal, Germany, allow a better understanding of these loads and the resulting (ship-induced) sediment transport. The measurements include high-resolution time series of pressure, three-dimensional flow velocities, and turbidity, collected using stationary as well as vessel-mounted sensors. The focus of this paper is on two aspects. First, existing drawdown estimation approaches are reviewed and validated against field measurements. Based on this, a new approach is derived to improve the general description of ship waves in confined waters. Second, a new approach to estimate the ship-induced sediment transport in the Kiel Canal is developed using turbidity and flow measurements and validated against dredging volumes. Our results show that about 10% of the total transported sediment volume in the Kiel Canal can be attributed to ship traffic, whereas the remaining volume is mainly transported during regular dewatering periods. This paper provides an empirical-based method to estimate ship-induced sediment transport in artificial waterways as basis for future canal management strategies.]]></description>
      <pubDate>Wed, 29 Apr 2020 17:42:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/1703366</guid>
    </item>
    <item>
      <title>A Fundamental Study on the Influence of the Backwash Due to Tsunamis upon the Mooring Vessel</title>
      <link>https://trid.trb.org/View/1637968</link>
      <description><![CDATA[When tsunamis attack the harbors, the first attack of tsunamis has two forms; leading waves and backwash. And, it is difficult to predict the form of the first attack of tsunamis. Also, because leading waves and backwash are alternated in tsunami, it is necessary that damage protection measures of mooring vessels against both leading waves and backwash are considered. Authors have been mainly studying about damage protection measures of mooring vessels against the leading waves. However, backwash have hardly been studied. In this study, the influence of backwash against mooring vessels at a wharf was examined. The three dimensional MPS (Moving Particle Semi-implicit) method was used. Backwash was expressed as the dam break phenomenon. Outflow angle, flow velocities and mooring conditions were considered. As a result, a safety of the mooring against backwash was evaluated.]]></description>
      <pubDate>Mon, 21 Oct 2019 09:46:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/1637968</guid>
    </item>
    <item>
      <title>Development of Empirical Formulation for Bow Flare Slamming and Deck Wetness for Displacement Vessels</title>
      <link>https://trid.trb.org/View/1579066</link>
      <description><![CDATA[The paper presents an empirical method to calculate bow flare slamming pressure and the green water load. Many empirical formulae for various types of vessels have been provided by rules of ship classification societies. In the present work, attempt is made to develop generalized formulations for all types of displacement vessels. Extreme sea conditions are considered. Bow flare pressure is derived in terms of flare and waterline angles. Specific condition for limiting waterline angle is derived based on 2D numerical simulations. Deck wetness is derived in terms of static and dynamic swell-up and the relative motion. Variation of static swell along the length is determined based on potential solution based analyses considering variation in vessels’ hull. 2D wedge simulations are carried out to validate the formulation of dynamic swell-up. Results of the calculated bow flare and deck pressures are compared with various ship classification society formulations and the trends are found to be in good agreement in general barring at bow flare where lower pressure is found in most of the presented cases. Also IACS UR S21A (2018) governing minimum pressure for deck scantlings is found to be conservative in few of the presented cases. Although scantlings assessment is not performed, the presented new formulations may help in realistic assessment of scantlings.]]></description>
      <pubDate>Thu, 21 Feb 2019 09:55:02 GMT</pubDate>
      <guid>https://trid.trb.org/View/1579066</guid>
    </item>
    <item>
      <title>Numerical Investigation of Green Water Loading on Flexible Structures using Three-Step CFD-BEM-FEM Approach</title>
      <link>https://trid.trb.org/View/1579058</link>
      <description><![CDATA[In this paper, the effect of green water impact on a flexible structure is studied based on three-step computational fluid dynamics (CFD)–boundary element method (BEM)–finite element method (FEM) approach. The impact due to shipping of water on the deck of the vessel is computed using commercial CFD software and used as an external force in coupled BEM-FEM solver. Other hydrodynamic forces such as radiation, diffraction, and Froude-Krylov forces acting on the structure are evaluated using 3D time domain panel method. To capture the structural responses such as bending moment and shear force, 1D finite element method is developed. Moreover, a direct integration scheme based on the Newmark–Beta method is employed to get the structural velocity, displacement, etc., at each time step. To check the effect of the green water impact on the structure, a rectangular barge without forward speed is taken for the analysis. The influence is studied in terms of bending moment, shear force, etc. Results show that the effect of green water impact on the bow region can be severe in extreme seas and lead to various structural damages. Similarly, it is also verified that vessel motion affects green water loading significantly and therefore one must consider its effect while designing a vessel.]]></description>
      <pubDate>Thu, 21 Feb 2019 09:55:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/1579058</guid>
    </item>
    <item>
      <title>Computer and Experimental Simulations on the Fin Effect on Ship Resistance</title>
      <link>https://trid.trb.org/View/1498815</link>
      <description><![CDATA[Container ships move at a higher speed compared to other merchant ship types. A fin attached to the ship hull proves to be more efficient in controlling the moving ship. However, such attachments on the naked hull attract additional problems such as slamming, requirement of continuous maintenance, etc. The main objective of this study is to find the influence of fin action at various angles of attack with the incoming flow and recommend the best possible fin position for the least resistance. While experiments were performed for different angles of attacks of the fin with respect to the flow, a reduction in resistance was observed for an Fn range of 0.13–0.26. The fin was fitted at the lowest possible location of the hull surface at the bow part of the ship. Experimental investigation was done using model tests in a towing tank to determine the resistance of a scaled down model and it was compared with computer simulation. The interaction of a bow fin fitted to a container ship with its own generated and encountering waves are discussed in this paper. It was observed that at certain angles of attack of the fins favourable resistance characteristics were observed. Modifications from the expected resistance due to fin effect are paid attention in this study. Various resistance values for different angles of attack of the fin were compared and an angle of attack of 5° is found to be the best.]]></description>
      <pubDate>Fri, 22 Jun 2018 16:40:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/1498815</guid>
    </item>
    <item>
      <title>Experimental Study of Bubble Sweep-down in Wave and Current Circulating Tank: Part I—Experimental Set-up and Observed Phenomena</title>
      <link>https://trid.trb.org/View/1409472</link>
      <description><![CDATA[Bubble sweep-down is a significant issue for the oceanographic vessels, which affect the acoustic surveys. Experimental trials, carried out in the Ifremer wave and current circulating tank on a 1/30 model of the Pourquoi pas?, are presented. The results demonstrate that this kind of experimental facility is well suited to study the phenomenon of bubble sweep-down encountered around the bow of a ship under specific conditions. From these results, two kinds of bubble clouds formation have been observed and analysed: bubble clouds generated by vortex shedding and breaking waves. The vortex shedding bubble clouds appear randomly in all the configurations tested, even without waves or motions. This phenomenon is due to the interaction between the turbulent flow and the specific bow shape of the Pourquoi pas?. On the other hand, the breaking wave clouds appear in the presence of relative motions between the free surface and the bow ship and more significantly under wave sollicitations. A complementary paper presents a parametric study carried out to quantify the influence of the test conditions.]]></description>
      <pubDate>Tue, 28 Jun 2016 16:17:02 GMT</pubDate>
      <guid>https://trid.trb.org/View/1409472</guid>
    </item>
    <item>
      <title>Experimental Investigation of the Effect of Bow Profiles on Resistance of an Underwater Vehicle in Free Surface Motion</title>
      <link>https://trid.trb.org/View/1344508</link>
      <description><![CDATA[In this paper, towing tank experiments are conducted to study the behavior of flow on a model of the underwater vehicle with various shapes of bows, i.e. tango and standard bows in free surface motion tests. The total resistances for different Froude numbers are considered experimentally. The towing tank is equipped with a trolley that can operate in through 0.05–6 m/s speed with ±0.02 m/s accuracy. Furthermore, the study is done on hydrodynamic coefficients i.e. total, residual and friction resistance coefficients, and the results are compared. Finally, the study on flow of wave fields around bows is done and wave filed around two bows are compared. The Froude number interval is between 0.099 and 0.349. Blockage fraction for the model is fixed to 0.005 3. The results showed that the residual resistance of the standard bow in 0.19 to 0.3 Froude number is more than the tango bow in surface motion which causes more total resistance for the submarine. Finally, details of wave generated by the bow are depicted and the effects of flow pattern on resistance drag are discussed.]]></description>
      <pubDate>Thu, 26 Feb 2015 09:53:59 GMT</pubDate>
      <guid>https://trid.trb.org/View/1344508</guid>
    </item>
    <item>
      <title>Physics-Based Learning Models for Ship Hydrodynamics.</title>
      <link>https://trid.trb.org/View/1247390</link>
      <description><![CDATA[The authors present the concepts of physics-based learning models (PBLM) and their relevance and application to the field of ship hydrodynamics. The utility of physics-based learning is motivated by contrasting generic learning models for regression predictions, which do not presume any knowledge of the system other than the training data provided with methods such as semi-empirical models, which incorporate physical insights along with data-fitting. PBLM provides a framework wherein intermediate models, which capture (some) physical aspects of the problem, are incorporated into modern generic learning tools to substantially improve the predictions of the latter, minimizing the reliance on costly experimental measurements or high-resolution high-fidelity numerical solutions. To illustrate the versatility and efficacy of PBLM, the authors present three wave-ship interaction problems: 1) at speed waterline profiles; 2) ship motions in head seas; and 3) three-dimensional breaking bow waves. PBLM is shown to be robust and produce error rates at or below the uncertainty in the generated data at a small fraction of the expense of high-resolution numerical predictions.]]></description>
      <pubDate>Fri, 26 Apr 2013 08:36:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/1247390</guid>
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