<rss version="2.0" xmlns:atom="https://www.w3.org/2005/Atom">
  <channel>
    <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" />
    <description></description>
    <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>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
    </image>
    <item>
      <title>BRIDGE FLUTTER DERIVATIVES AT VORTEX LOCK-IN</title>
      <link>https://trid.trb.org/View/485939</link>
      <description><![CDATA[Many structures with extended spans undergo the flow-induced oscillation commonly called vortex shedding.  In the case of long-span bridges, Ehsan and Scanlan, employing basic data from deck section wind tunnel model tests, offered a nonlinear theoretical framework for predicting maximum vortex-induced amplitude under the lock-in condition.  The present paper replaces the Ehsan-Scanlan model with a linearized form that brings it into conformity with the familiar flutter derivative expressions now commonly used in bridge wind-stability analyses. The essential new addition is an active sinusoidal lift term. Converting some of the Ehsan-Scanlan experimental section data to the new form, the suggested replacement model successfully reidentifies the range of original Tacoma Narrows vortex-induced response amplitudes that were experimentally obtained by Farquharson on a full-bridge model.  Either vertical or torsional motions at vortex lock-in can be assayed by the method discussed.]]></description>
      <pubDate>Wed, 06 May 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/485939</guid>
    </item>
    <item>
      <title>FUNDAMENTAL STUDY ON THE NEW METHOD TO ESTIMATE VIBRATION LEVEL ON A SHIP (FORMULATION OF THE DAMPING MATRIX BASED ON DISSIPATION ENERGY CAUSED BY FLUID VISCOSITY)</title>
      <link>https://trid.trb.org/View/480533</link>
      <description><![CDATA[In this paper, a new theory of added damping matrix based on dissipation energy caused by fluid viscosity is described.  The distribution of flow velocity in the vibrational boundary layer is determined by assuming laminar flow in spite of the existence of turbulence, then shearing stress is decided using virtual kinematic viscosity coefficient.  Dissipation energy caused by fluid viscosity is formulated as the function of the nodal amplitude of the BEM mesh model.  The added damping matrix can be obtained by comparison with the dissipation energy of the usual damping matrix of FEM.  The difference of dissipation energy between deep water and shallow water is clarified by using the added damping matrix.  A new idea of reduced added damping matrix is defined, then combination analysis of the experimental modal analysis and BEM is executed using the reduced added mass and damping matrix.  The validity of the added damping matrix is verified by comparison with experiments in deep water and shallow water.]]></description>
      <pubDate>Thu, 27 Mar 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/480533</guid>
    </item>
    <item>
      <title>A STUDY ON THE EFFECT OF MEASUREMENT POINTS UPON REDUCED ADDED MASS MATRIX</title>
      <link>https://trid.trb.org/View/480534</link>
      <description><![CDATA[A new method of combination analysis using experimental modal analysis and BEM was developed by the authors.  To use this new method, the effect of arrangement of the measurement points upon the solution of the modal-BEM combinational analysis must be explained.  In this paper, the effect is explained by some concrete parametric calculations on an ellipsoid of revolution.  As the result of analysis on the calculations, 21 points distribution at regular intervals is enough for the number of the observation points to apply the method to the vertical bending vibration mode even below 4 node. Then the effect of rotation vector is analyzed, it is explained that the accuracy of the solution without considering the rotation vector cannot be better than on higher vibration mode, if many observation points are set.  This is verified by comparison with experiments in deep water and shallow water.]]></description>
      <pubDate>Thu, 27 Mar 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/480534</guid>
    </item>
    <item>
      <title>SIMULATIONS OF FLOW OVER A FLEXIBLE CABLE: A COMPARISON OF FORCED AND FLOW-INDUCED VIBRATION</title>
      <link>https://trid.trb.org/View/480734</link>
      <description><![CDATA[The paper presents results of direct numerical simulation from an on-going investigation of flow over a flexible cable.  In particular, the forced cable vibration is compared with flow-induced cable vibration at Reynolds numbers 100, 200 and 300.  The cables are assumed to be infinitely long and periodic, two spanwise wavelength cases were chosen: the "short" cable (L/d = 12.6), and the "long" cable (L/d = 45).  The dynamics of the cable, concentrating on lift forces and the power produced by these lift forces were examined. Then the flow structures in the wake of the vibrating cable were examined.  A breakdown of a time-periodic cable and wake response going from Re = 100 to Re = 200 was observed.  At Re = 100 relatively similar responses were observed comparing the forced vibration case with the flow-induced vibration case, but at Re = 200 differences become larger.  Finally, a comparison with the experimental results of forced vibration by Ramberg and Griffin is presented.]]></description>
      <pubDate>Thu, 27 Mar 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/480734</guid>
    </item>
    <item>
      <title>A DEMONSTRATION OF ADAPTIVE LEAST-MEAN-SQUARE CONTROL OF SMALL AMPLITUDE VORTEX-INDUCED VIBRATIONS</title>
      <link>https://trid.trb.org/View/480992</link>
      <description><![CDATA[Small amplitude vortex-induced vibrations of flexible cylinders are controlled using a robust adaptive Least Mean Square (LMS) algorithm.  The algorithm, with its adaptive control capabilities, provides an excellent means of rejecting the effect of the periodic vortex-induced excitations which act persistently on the flexible cylinders.  It is also capable of accommodating a considerable amount of uncertainty of the structural parameters of the vibrating cylinders.  The LMS control action is developed using a hot-wire anemometer placed in the wake of the cylinder to generate a reference signal which is indicative of the vortex-shedding excitation. The resulting signal is manipulated and fed forward to minimize the structural vibration at critical locations.  In this manner, the LMS method presents a simple yet powerful alternative to classical control methods for disturbance-counteracting laws.  The effectiveness of the LMS controller in suppressing small amplitude vortex-induced vibrations of flexible cylinders is demonstrated experimentally at various flow conditions.  The effect of the design parameters of the LMS controller on its performance is also investigated.  The results obtained emphasize the potential of the LMS method as an effective and robust means for attenuating undesirable vortex-induced vibrations.]]></description>
      <pubDate>Thu, 27 Mar 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/480992</guid>
    </item>
    <item>
      <title>VORTEX-INDUCED VIBRATION ANALYSIS OF THE AUGER TLP PRODUCTION AND STEEL CATENARY EXPORT RISERS</title>
      <link>https://trid.trb.org/View/467291</link>
      <description><![CDATA[This paper describes the methodology used to analyze the Auger tension leg platform production and steel catenary export risers for vortex-induced vibrations.  Presented are: 1) a discussion of the development of testing facilities for deepwater riser vortex- induced vibration modelling; 2) an overview of the tests used to calibrate a response prediction program; 3) calibration of the response prediction program; 4) the analysis procedure for both riser types; 5) the analyses' results; and 6) a summary of the vortex suppression technology used to choose triple-start helical strakes for the export risers.]]></description>
      <pubDate>Mon, 04 Nov 1996 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/467291</guid>
    </item>
    <item>
      <title>HETEROCLINIC BIFURCATIONS IN FLOW-INDUCED OSCILLATIONS OF CYLINDERS</title>
      <link>https://trid.trb.org/View/467296</link>
      <description><![CDATA[The transition of flow-induced cylinder vibrations to chaos in terms of heteroclinic bifurcations is investigated.  The approach is based on a modified version of a model presented in a previous paper (Berger & Plaschko 1993).  It is shown that these bifurcations occur along a locus given in terms of mass-ratio versus wind-speed curve and the transition to chaos is interpreted using energy arguments.]]></description>
      <pubDate>Mon, 04 Nov 1996 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/467296</guid>
    </item>
    <item>
      <title>FLOW-INDUCED VIBRATION OF TUBES IN CROSSFLOW</title>
      <link>https://trid.trb.org/View/456541</link>
      <description><![CDATA[This paper presents an unsteady-flow theory for flow-induced vibration of tubes in crossflow.  It includes a general description of motion-dependent fluid forces, characteristics of fluid-force coefficients, and mathematical model.  Detailed results are presented for the constrained mode in the lift direction for various tube arrangements.]]></description>
      <pubDate>Wed, 27 Mar 1996 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/456541</guid>
    </item>
    <item>
      <title>ERROR ESTIMATION OF FLUID PRESSURE USING SINGULAR POINT METHOD</title>
      <link>https://trid.trb.org/View/456765</link>
      <description><![CDATA[The usefulness and accuracy of the Singular Point Method (SPM) for the problem of structural vibration in contact with fluid is reported.  The accuracy of the SPM is confirmed in the fluid pressure problem which is solved theoretically, however it is necessary to estimate the error of the fluid pressure calculation in case of no theoretical and experimental value.  In this paper, the author shows the method for error estimation of fluid pressure using the SPM.  A different method should be used to estimate the error in the case of Source and Doublet.  In the calculation model which can be estimated theoretically, good accuracy can be estimated, however the actual structure was checked.]]></description>
      <pubDate>Wed, 27 Mar 1996 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/456765</guid>
    </item>
    <item>
      <title>UNSTEADY FLUID FORCES ACTING ON TWO TANDEM CIRCULAR CYLINDERS SUBJECTED TO TWO-PHASE CROSS-FLOW</title>
      <link>https://trid.trb.org/View/455643</link>
      <description><![CDATA[To understand the excitation and suppression effects of air bubbles on the vibration of two tandem cylinders, experimental investigations were carried out on the characteristics of unsteady fluid force in the lift direction acting on the downstream cylinder having a pitch-to- diameter ratio of 3.0 and subjected to two-phase bubble cross-flow. The average diameter of bubbles is about 3 to 4 mm.  Experiments to measure the unsteady fluid force are performed, changing the void fraction at three different reduced velocities (2.15, 4.88, and 7.05) for oscillation amplitudes ranging from 5.0 to 15.0 mm.  The downstream cylinder is forced to oscillate sinusoidally at the natural frequency of the upstream cylinder in water.  Experiments reveal the following major characteristics of fluid force: 1) at low reduced velocity, almost no difference is observed in the characteristics with respect to void fraction and oscillation amplitude; 2) air bubbles reduce the fluid force in the range of the void fraction     5% and at a small oscillation amplitude for the lock-in state reduced velocity; and 30 at high reduced velocity, unsteady fluid force increases with void fraction.]]></description>
      <pubDate>Mon, 04 Mar 1996 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/455643</guid>
    </item>
    <item>
      <title>STUDY ON THE VIBRATIONAL CHARACTERISTICS OF A TUBE ARRAY CAUSED BY TWO-PHASE FLOW. PART 1: RANDOM VIBRATION</title>
      <link>https://trid.trb.org/View/455648</link>
      <description><![CDATA[This paper presents the experimental results on turbulent buffeting forces generated both by air-water flow and by steam-water two-phase flow for the extreme pressure conditions up to 5.8 MPa and temperatures reaching 272oC, the explanation of the mechanism producing these forces, and a method for evaluating tube response caused by two-phase flow.  The main source of the buffeting forces in slug or froth two-phase flow is recognized to be the impact forces caused by the intermittently rising water slugs.  The slug speed and the fluid forces acting on a tube are estimated, together with an estimation of the period of the occurrence of the rising water slug. The accuracy of this estimation method is proved by comparing the theoretical response with the measured one.]]></description>
      <pubDate>Mon, 04 Mar 1996 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/455648</guid>
    </item>
    <item>
      <title>STUDY ON THE VIBRATIONAL CHARACTERISTICS OF A TUBE ARRAY CAUSED BY TWO-PHASE FLOW. PART II: FLUIDELASTIC VIBRATION</title>
      <link>https://trid.trb.org/View/455649</link>
      <description><![CDATA[This paper presents experimental results on the fluidelastic vibration caused by air-water flow and by steam-water two-phase flow in conditions of up to 7.0 MPa pressure and temperatures reaching 284oC.  A new criterion, based on an assumption of energy balance per cycle of oscillation, is introduced using the "true" flow velocity.  However, comparison with the experimental data indicates that, in the slug or froth flow regimes, the speed of the intermittently rising slugs, introduced in Part I of this study, should be used; hence, a new modified criterion for the slug and froth flow regimes is derived.  In addition, the new criterion is compared with the usual Connors-type criterion which greatly depends on the estimation of the damping in two-phase flow.  The agreement between the two criteria is found to be within the uncertainty introduced by the variance in the unknown parameters in the Connors criterion.]]></description>
      <pubDate>Mon, 04 Mar 1996 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/455649</guid>
    </item>
    <item>
      <title>MECHANISM AND FEATURES OF FREQUENCY SPECTRUM OF PROPELLER SINGING</title>
      <link>https://trid.trb.org/View/455051</link>
      <description><![CDATA[A simplified physical model of the sound field radiated by rotating propeller blades which produce singing is given for both the full-scale propeller and model propeller tested in a water tunnel.  The theoretical analysis and experimental results indicate that the signal of propeller singing received at field point out of the direction of the propeller shaft is a superposition of a series of sound waves with frequencies fn = fs + n OMEGA / 2 pi (fs - vibration frequency of rotating propeller blades), while in the direction of the propeller shaft is a tone with single frequency f.  The features of frequency spectrum are verified for both the full scale propeller and the model propeller.]]></description>
      <pubDate>Wed, 28 Feb 1996 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/455051</guid>
    </item>
    <item>
      <title>UNSTEADY ANNULAR VISCOUS FLOWS BETWEEN OSCILLATING CYLINDERS. PART I; COMPUTATIONAL SOLUTIONS BASED ON A TIME-INTEGRATION METHOD</title>
      <link>https://trid.trb.org/View/455106</link>
      <description><![CDATA[The paper presents 2-D and 3-D computational solutions for unsteady annular viscous flows with oscillating boundaries.  A time- integration method based on a three-time-level implicit semi- discretization is first formulated in cylindrical coordinates for solving the time-dependent incompressible Navier-Stokes equations.  This method uses a pseudo-time integration with artificial compressibility to advance the solution between consecutive real time levels, and a finite-difference spatial discretization based on a stretched staggered gird.  A decoupling procedure based on a factored ADI scheme with lagged nonlinearities reduces the problem to the solution of scalar tridiagonal systems.  As a result, this method displays very good computing efficiency and accuracy in all numerical examples analyzed.  The method is first validated for axisymmetric flow over an annular backstep, by comparison with previous results, and is then employed to analyze 2-D unsteady annular flows due to transverse oscillations of the outer boundary.  The results obtained with this method are free of spurious, numerically induced, oscillations in the unsteady pressure, which otherwise arise if a Crank-Nicolson scheme is used instead for time-discretization.  The 3-D case of oscillating boundaries in annular axial flow is also analyzed with this method by considering a fully developed viscous flow between two concentric cylinders when the central portion of the outer cylinder executes transverse translational oscillations; the computational solution thus obtained is of interest in the study of flow-induced vibration problems in such configurations.  See also the following abstract.]]></description>
      <pubDate>Wed, 28 Feb 1996 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/455106</guid>
    </item>
    <item>
      <title>UNSTEADY ANNULAR VISCOUS FLOWS BETWEEN OSCILLATING CYLINDERS. PART II: A HYBRID TIME-INTEGRATION SOLUTION BASED ON AXIMUTHAL FOURIER EXPANSIONS FOR CONFIGURATIONS WITH ANNULAR BACKSTEPS</title>
      <link>https://trid.trb.org/View/455107</link>
      <description><![CDATA[A hybrid time-integration method based on aximuthal Fourier expansions for solving the time-dependent incompressible Navier- Stokes equations has been developed in order to obtain superior computational efficiency; this will permit the simultaneous time- integration of the coupled systems of equations of fluid and structural unsteady motions.  The hybrid method uses highly convergent Fourier expansions in the aximuthal angular coordinate for the unsteady pressure and velocity components while maintaining the same efficient finite-difference formulation for time and the axial and radial spatial coordinates as in the basic time-integration method previously developed (see the previous abstract).  This method has been first applied for validation to several 2-D and 3-D unsteady flows in annular passages with oscillating boundaries, leading to solutions which were found to be in very good agreement with the results obtained with the basic method for 3-D unsteady flow in nonuniform annular passages with an annular backstep, and with oscillating boundaries.  The hybrid method displays excellent computational efficiency, at least one order of magnitude better than the basic time-integration method (itself very efficiency) in all cases tested; hence, this method is well suited for eventual use in the simultaneous time-integration of the coupled systems of equations in fluid-structure interaction problems.]]></description>
      <pubDate>Wed, 28 Feb 1996 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/455107</guid>
    </item>
  </channel>
</rss>