<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>An Explorative Study to Use Super-Hydrophilic/Super-Hydrophobic Hybrid Surfaces for Aircraft Icing Mitigation</title>
      <link>https://trid.trb.org/View/1631285</link>
      <description><![CDATA[An explorative study was performed to demonstrate the feasibility of using a novel hybrid anti-/de-icing strategy for aircraft icing mitigation. The hybrid method was developed by combining the electro-thermal heating mechanism and specialized surfaces/coatings with different wettabilities. While an electrical film heater was utilized to provide thermal energy around the leading edge of a NACA0012 airfoil model, two different coating strategies, (i.e., (a). Superhydrophobic coating covering the entire airfoil surface to increase droplets bounce-off and accelerate surface water runback vs. (b). super-hydrophilic coating at the leading edge to increase evaporation area + superhydrophobic coating in downstream to prevent runback refreezing) were proposed and evaluated aiming at maximizing the anti-/de-icing efficiency of the hybrid method. While a series of experiments were conducted to examine the dynamics of droplet impinging onto the different surfaces (i.e., superhydrophobic vs. super-hydrophilic), a comprehensive experimental study was carried out in the Icing Research Tunnel at Iowa State University (i.e., ISU-IRT) to evaluate the anti-/de-icing performance of the hybrid method with the different coating strategies. It was found that, while both of the coating strategies could promote better anti-/de-icing performance of the hybrid method in comparison to the conventional heating-only method at rime ice condition. For glazed ice condition, the use of superhydrophobic coating over the entire airfoil surface would result in a maximized anti-/de-icing efficiency of the hybrid method (i.e., achieve a complete ice prevention with only 3% chord length covered with the electrical film heater), attributing to the significant droplets bounce-off and accelerated surface water runback behaviors.       ]]></description>
      <pubDate>Mon, 22 Jul 2019 10:32:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/1631285</guid>
    </item>
    <item>
      <title>Reduced-Order Modeling of Unsteady Aerodynamics for an Elastic Wing with Control Surfaces</title>
      <link>https://trid.trb.org/View/1420771</link>
      <description><![CDATA[In this paper, a reduced-order modeling approach based on computational fluid dynamics is presented for an elastic wing with control surfaces in the transonic regime. To treat the computational fluid dynamics grid around the geometrical discontinuities, due to the deflection of control surfaces, the constant volume tetrahedron method and the transpiration method are combined together without deforming the grid. Based on the input–output data from the computational fluid dynamics solver, one multiple-input/multiple-output discrete-time state-space model for the wing is identified via a robust subspace algorithm. For each control surface, one one-input/multiple-output discrete-time state-space model is identified using the same algorithm. With the precomputed state-space models for a few flight parameters, the generalized aerodynamic forces over a range of flight parameters can be computed by interpolating the output data. The methodology is applied to an elastic wing model with two control surfaces and the generalized aerodynamic forces are compared with the results from the computational fluid dynamics solver to validate the reduced-order modeling approach in transonic regime.]]></description>
      <pubDate>Fri, 30 Sep 2016 16:32:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/1420771</guid>
    </item>
    <item>
      <title>Validation of Tab Assisted Control Surface Computation</title>
      <link>https://trid.trb.org/View/1138463</link>
      <description><![CDATA[A numerical procedure for the prediction of the forces and moments of a tab assisted control surface (TAC) has been developed. The control surface consists of a stern stabilizer, a flap, and a tab. The numerical procedure is based on solving the incompressible Reynolds-averaged Navier-Stokes equations coupled with several two-equation turbulence models. Some features of the numerical method used have been highlighted. In particular, the preconditioning method, multigrid method, and nonreflecting far field boundary condition have been discussed. The wall boundary condition for the specific dissipation rate which is important in obtaining good convergence for the -ω equation turbulence model have also been briefly discussed. Computed results of the lift and drag coefficients of the control surface, flap torque coefficients and tab torque coefficients at various angles of attack of the stabilizer and of flap angles and tab angles have been predicted within 10 percent from the measured values even at high angles of attack at 15 degrees. The discrepancies of the torque coefficients of flap and tab are somewhat higher particularly at high flap and torque deflections. There are two reasons for these higher discrepancies. The first reason is that the turbulence models are inherently weak in the flow regime where separation is severe, and the second is that the grid solution in both the flap and tab gap is not sufficient. These will be the topics for future investigations.]]></description>
      <pubDate>Fri, 11 May 2012 09:05:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/1138463</guid>
    </item>
    <item>
      <title>Engineered Materials Arresting System : a pilot's primer</title>
      <link>https://trid.trb.org/View/1098468</link>
      <description><![CDATA[]]></description>
      <pubDate>Fri, 01 Apr 2011 10:41:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/1098468</guid>
    </item>
    <item>
      <title>EFFECTS OF ASPECT RATIO, SECTION SHAPE, AND REYNOLDS NUMBER ON THE LIFT AND DRAG OF A SERIES OF MODEL CONTROL SURFACES; FINAL REPT</title>
      <link>https://trid.trb.org/View/411231</link>
      <description><![CDATA[The report presents the results of towing tank tests on a series of fins, representative of the canards on a SWATH vessel or the rudders on a planing hull. The work was done to determine whether or not the fins and rudders on a small model suffered from serious scale effects. Fins with aspect ratios of 1.0, 1.5 and 2.0 were mounted vertically under a horizontal flat plate and towed at a series of speeds resulting in five Reynolds numbers, based on chord length, between 42,000 and 150,000.  The fins had both flat plate and NACA 0015 cross sections, and were tested with and without turbulence trips. Lift and drag forces were measured at a series of angles of attack which were varied from 0 to 35 degrees in five degree increments. The measured lift slopes agreed well with predictive equations developed at DTNSRDC for fins at high Reynolds numbers. This means that dynamic stability and course keeping data taken using small models can be used in making full scale predictions. Control surfaces, Reynolds number effects, Fins, Turbulence trips, SWATH Control, Rudders, Aspect ratio effects.]]></description>
      <pubDate>Fri, 11 Jan 2002 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/411231</guid>
    </item>
    <item>
      <title>EXPERIMENTAL STUDY OF AN AUTOMATIC PITCH CONTROL SYSTEM ON A SWATCH MODEL; FINAL REPT</title>
      <link>https://trid.trb.org/View/411229</link>
      <description><![CDATA[The report presents the results of a series of tests which was carried out in order to develop a small physical model of an automatic pitch control system for a SWATH ship, and to study the interaction of the control surface with the twin hulls in calm water and regular waves. A four phase test program was followed to assess the control system:  fixed trim, free to heave tests of the unappended hull, tests of isolated canards, fixed trim tests in calm water and in waves with instrumented canards, and free to trim and heave tests in regular waves with and without automatic control. Drag, pitching moment, canard lift and drag, etc., were measured and analyzed. The maximum lift on the canards in waves was found to be significantly larger than that measured in static tests. Results are presented in graphic and tabular form. Tests in regular waves with pitch control showed that a 50% reduction in pitch amplitude is possible in following seas. SWATH, Automatic control, Unsteady lift, Control surfaces, Seakeeping.]]></description>
      <pubDate>Fri, 11 Jan 2002 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/411229</guid>
    </item>
    <item>
      <title>NUMERICAL SIMULATION OF A CONTROL SURFACE BEHAVIOUR BY A FORCE FIELD</title>
      <link>https://trid.trb.org/View/480744</link>
      <description><![CDATA[The paper presents a method for including the effect of fins in 3D Navier-Stokes calculations using simplified computation grids. This method offers advantages in terms of fin force control and unsteady flow calculations.  The principle of the method is briefly presented and preliminary results are shown for 2D and 3D cases. The results show that the velocity fields created by the force field can be similar to those computed based on a fully meshed fin.]]></description>
      <pubDate>Thu, 27 Mar 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/480744</guid>
    </item>
    <item>
      <title>A CONCEPTUAL DESIGN STUDY OF THE CONSTRUCTION OF HYDRODYNAMIC CONTROL SURFACES</title>
      <link>https://trid.trb.org/View/449060</link>
      <description><![CDATA[Hydrodynamic control surfaces are traditionally built as steel fabrications.  While this gives a very strong structure, it is rather heavy and costly, it is difficult to achieve smooth surfaces, and the steel is susceptible to erosion, corrosion and marine fouling.  This paper describes a conceptual design study aimed at creating a competitive advantage for the manufacturers of control surfaces by using modern materials in a composite structure.  The conceptual design process, as applied in the paper, starts by specifying the design requirements for the construction of control surfaces and listing a set of criteria gainst which the concept designs can be evaluated.  A total of six concept designs are described and evaluated in comparison with a traditional steel fabrication, and one concept is selected for further development.  This comprises a light steel frame structure with thin steel inner face plates enclosing an inner core that is filled with polyurethane foam.  The surface shape is also formed with polyurethane foam poured between the face plates and a surface mould plate.  Finally, the surface is sprayed with a polyurethane elastomer coating.]]></description>
      <pubDate>Mon, 14 Aug 1995 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/449060</guid>
    </item>
    <item>
      <title>A NEW APPROACH TO OPTIMISING FUEL ECONOMY FOR SHIPS IN A SEAWAY</title>
      <link>https://trid.trb.org/View/439343</link>
      <description><![CDATA[When a ship is moving in a seaway its increased motion,particularly in pitch and heave, produces additional resistance.  The ship's master therefore has two choices, he can: (a) maintain the same engine power and travel at slower forward speed or (b) increase the engine power to maintain his forward speed.  This paper considered pitch and heave stabilisation by the use of control surfaces as currently employed in submarines and aircraft.  A 5-degree of freedom model of a 17,000 tonne vessel is used to simulate a passage through hard seas that are characterised by a Pierson Moskowitz sea spectrum.  It is demonstrated that an optimal control algorithm may be used to control the ship's motion in such a manner that added resistance due to waves, and hence fuel costs are minimised.]]></description>
      <pubDate>Mon, 14 Aug 1995 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/439343</guid>
    </item>
    <item>
      <title>MOVING SURFACE BOUNDARY-LAYER CONTROL AS APPLIED TO TWO-DIMENSIONAL AIRFOILS</title>
      <link>https://trid.trb.org/View/438720</link>
      <description><![CDATA[The concept of moving surface boundary-layer control, as applied to a Joukowsky airfoil, is investigated through an experimental program complemented by a flow visualisation study. The moving surface was provided by rotating cylinders located at the leading edge and upper surface of the airfoil. The results suggest that the leading-edge rotating cylinder effectively extends the lift curve without substantially affecting its slope, thus increasing the maximum lift and delaying stall. When used in conjunction with a second cylinder on the upper surface, further improvements in the maximum lift and stall angle are possible. The maximum coefficient of lift realised was around 2.73, approximately three times that of the base airfoil. The maximum delay in stall was around 48 deg. In general, the performance improves with an increase in the ratio of cylinder surface speed Uc to the freestream speed U.]]></description>
      <pubDate>Mon, 14 Aug 1995 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/438720</guid>
    </item>
    <item>
      <title>MARINE PROPULSION UNIT WITH CONTROLLED CYCLIC AND COLLECTIVE BLADE PITCH; PATENT</title>
      <link>https://trid.trb.org/View/405983</link>
      <description><![CDATA[An integral marine propulsion unit utilizes both collective and cyclic propeller blade pitch angle variations to generate a thrust vector in any of three degrees of motion for use with both the submersible and surface marine vessels. The present marine propulsion unit eliminates the need for extraneous drag generating control surfaces and rudders for motion control of a marine vessel by incorporating a flat plate mechanism which includes an Oldham coupler coupled to a pair of plates and a slotted plate coupled with one of the plates. The slotted plate and the one plate coupled to the slotted plate are relatively rotatable about a fixed axis. The flat plate mechanism permits relative angular displacement between the slotted plate and the one plate to collectively pivot all of the propeller blades and permits radial movement of the slotted plate along with propeller blades.]]></description>
      <pubDate>Mon, 03 Oct 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/405983</guid>
    </item>
    <item>
      <title>SUBMARINE DRONE FOR CARRYING A BARREL STAVE-TYPE TRANSDUCER ARRAY; PATENT</title>
      <link>https://trid.trb.org/View/406165</link>
      <description><![CDATA[A submarine drone has special hydrodynamic performance features for operating as a moving underwater platform for underwater transport of a barrel stave type sonar receiving transducer and a pole type sonar transmitting transducer with highly precise vertical alignment. The body of the submarine comprises a generally spherical pressure hull for containing propulsion plant and electronic components. The barrel stave transducer is affixed about the upper half of the pressure hull. An acoustically transparent false walls form a spherical hydrodynamic wall over the pressure vessel and transducer. The false wall also forms a tail cone projecting from the rear side of the submarine. The tail cone contains an annular channel which takes in boundary layer water from the spherical portion of hydrodynamic wall and conducts it back to a pump jet at the extreme rear of the tail cone. A fixed tail boom emerges from the center of the pump jet structure and extends rearwardly. Cruciform control surfaces append from the tail boom. The pole transducer projects from the top of the spherical body and has a freely pivoting fairing made of acoustically transparent material there about.]]></description>
      <pubDate>Mon, 03 Oct 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/406165</guid>
    </item>
    <item>
      <title>PROPELLER UNIT WITH CONTROLLED CYCLIC AND COLLECTIVE BLADE PITCH; PATENT</title>
      <link>https://trid.trb.org/View/406142</link>
      <description><![CDATA[An improved integral marine propulsion unit is disclosed that can generate a thrust vector in any of three degrees of motion. The unit uses both collective and cyclic propeller blade pitch angle variation to generate these thrusts. This unit obviates the need for control surfaces and rudders for motion control of a marine vessel. Additionally, this unit provides flexibility in external propulsor arrangements on a marine hull. The unit integrates the swash plate mechanism and actuators within the central bore of a ring type prime mover.]]></description>
      <pubDate>Mon, 03 Oct 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/406142</guid>
    </item>
    <item>
      <title>A PRELIMINARY INVESTIGATION INTO THE FORCES ACTING ON SUBMERGED BODY APPENDAGES</title>
      <link>https://trid.trb.org/View/401540</link>
      <description><![CDATA[A simple steady state-potential model was developed to calculate the forces acting on a fixed submerged body with appendages, or control surfaces, using a mixed singularity distribution method. Predictions derived from the model are compared with experimental data for pressure distributions and lift coefficients associated with control surfaces of differing aspect ratios.]]></description>
      <pubDate>Thu, 21 Jul 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/401540</guid>
    </item>
    <item>
      <title>THE EFFECTS OF REYNOLDS NUMBER, SECTION SHAPE, AND TURBULENCE STIMULATION ON THE LIFT OF A SERIES OF MODEL CONTROL SURFACES</title>
      <link>https://trid.trb.org/View/406517</link>
      <description><![CDATA[A series of model control surfaces with equal areas but varying aspect ratio was tested in a towing tank on a groundboard. The size of the fins, approximately three inches span and two inches chord, is typical of control surfaces used on models that are about five feet long. Lift and drag on the fins were measured over a range of angles of attack of 0 to 35 degrees. The tests covered a range of chord-based Reynolds numbers between 42,000 and 150,000. Two sets of fins were tested, one having flat-plate sections and the other having NACA 0015 sections. The fins were each tested with and without turbulence stimulation in the form of tape with a serrated leading edge placed at 5% of the local chord aft of the leading edge of the foil. The study has shown that the lift of the NACA 0015 fins was insensitive to Reynolds number in the range of the tests, and that the lift rates compare well with the results of previous tests carried out at high Reynolds numbers. Differences were noted in the characteristics of flat-plate and NACA 0015 fins, which would indicate that the use of flat plates in the place of foil-shaped fins to save model construction cost is not a good practice. Turbulence trips increased the measured drag, as expected, but also reduced the lift rate, most noticeably on the flat-plate fins.]]></description>
      <pubDate>Thu, 21 Jul 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/406517</guid>
    </item>
  </channel>
</rss>