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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>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
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    <item>
      <title>APPLICATION OF EMULSIFIED FUELS TO DIESEL AND BOILER PLANT</title>
      <link>https://trid.trb.org/View/143435</link>
      <description><![CDATA[The increasing world interest in the conservation of fossil liquid fuel resources together with the anti-pollution requirements of certain Governments has necessitated a reappraisal of combustion technology with particular emphasis on methods of improving engine efficiency.  Two main approaches are possible, (a) complete or partial redesign of the engine, or (b) improvement of the fuel combustion characteristics.  Of these alternatives, the former indicates long-term and relatively expensive development often involving radical design departures, e.g. Rankine and Stirling cycle utilisation, or in the simplest case the improvement of fuel atomisation and distribution by various measures.  In each case, additional complexity results in a questionable compromise in terms of fuel economy, power-to-weight ratio, emission control, reliability and maintenance.  Because of this, the use of fuel additives to achieve these aims is the more economical solution.  In particular, the technique of water injection has attracted new interest.  This paper reviews research over the past decade on the application of water injection to boilers, internal combustion engines and gas turbines, to demonstrate the benefits arising from the use of emulsified fuels.  The boiler and Diesel engine trials carried out in the course of the University of Newcastle's research programme on emulsified fuels are then described in detail. The results of burning mechanically emulsified fuels in a range of research and industrial Diesel engines are presented and discussed.  The paper concludes with an outline of the future programme and some comments on the theoretical aspects of the combustion of emulsified fuels. Order from BSRA as No. 51,988.]]></description>
      <pubDate>Tue, 27 Feb 2001 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/143435</guid>
    </item>
    <item>
      <title>DIESEL-STIRLING COMBINATION MAY IMPROVE EFFICIENCY</title>
      <link>https://trid.trb.org/View/161450</link>
      <description><![CDATA[As economic, environmental, and other forces continue to influence automotive design, attention focuses on the diesel engine with its minimal fuel usage at and near idle.  One diesel specialist expects improved injector designs to couple with silicon-based materials in advancing a small adiabatic engine with reduced emissions.  Absence of many cooling-related devices and higher exhaust gas temperatures may make higher efficiencies possible through exhaust-heated Stirling engine applications, downstream.]]></description>
      <pubDate>Thu, 21 May 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/161450</guid>
    </item>
    <item>
      <title>OPTIMISING STEAMSHIP PERFORMANCE. METHODS OF REDUCING FUEL CONSUMPTION IN TURBINE PLANTS</title>
      <link>https://trid.trb.org/View/166515</link>
      <description><![CDATA[In addition to part-power operation, steamship operators can take several other steps that will help achieve a further significant drop in fuel consumption.  These include general maintenance and tune-ups, optimizing the thermal cycle and redesigning equipment.  Simple tune-ups alone can result in a 5% fuel saving.  Optimizing the thermal cycle and redesigning equipment require somewhat more effort and investment, but together they can reduce the fuel rate by as much as 14%.  Order from NSFI as No. 22186.]]></description>
      <pubDate>Thu, 21 May 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/166515</guid>
    </item>
    <item>
      <title>ENERGY CONSERVATION FOR PROPULSION OF NAVAL VESSELS</title>
      <link>https://trid.trb.org/View/168473</link>
      <description><![CDATA[Energy conservation for powering of U.S. Navy surface ships continues to be of prime importance in their design. Depletion by consumption of world petroleum reserves, combined with rapidly rising petroleum fuel costs, intensifies the need for improving the efficiency of current gas turbine power plants.  Present gas turbine power plants, with a capacity adequate for naval ship propulsion, have a fuel consumption rate approaching 0.42lbs per brake horsepower-hour at full power.  Using a waste heat recovey unit, system studies show this can be reduced to less than 0.32lbs per brake horsepower-hour. This 24% reduction in fuel consumption rate all full power, or 35% at part power, can produce either a corresponding increase in cruising range (for the same fuel loading), or a reduction in the required fuel loading and tankage (for the same cruising range).  Therefore, to evaluate the merits of COGAS systems for U.S. Navy surface ship propulsion, a study was made to evaluate their benefits.  Ship impact studies and "trade-off" evaluations were completed.  The results show that ultimate fuel consumption rates of 0.28lbs per brake horsepower-hour at full power may be achieved, using large, efficient gas turbine units. This study also showed that in order to obtain this fuel consumption improvement, this system required additional space and weight.  Ship arrangements are also impacted. However, the effect on ship stability is slight.  The net gain justifies the use of COGAS propulsion in future U.S. Navy surface ships.]]></description>
      <pubDate>Thu, 21 May 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/168473</guid>
    </item>
    <item>
      <title>WAYS TO REDUCE SLOW STEAMING FUEL CONSUMPTION OF STEAM TURBINE MACHINERY THROUGH TECHNICAL MODIFICATIONS</title>
      <link>https://trid.trb.org/View/161802</link>
      <description><![CDATA[Over the past 5-6 years slow steaming has been a rather common mode of operation for a large number of ships, particularly ships with high propulsion power.  The underlying cause of this has been a very large rise in bunker fuel prices since 1973-74, while charter rates at the same time in general have stayed quite low.  A study has been performed of select configurations of steam turbine machinery to determine what fuel savings can be obtained, particularly at part load, through changes in method of operation or through technical modifications that for the most part are relatively moderate.  Results are presented in the form of percentage fuel savings and in terms of cost savings.  The savings may range from 0.5% to 10%.  With fuel oil prices at its present high level, a fuel reduction of only 0.5% may represent a large annual cost saving well worth making an effort to achieve.]]></description>
      <pubDate>Sat, 29 Nov 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/161802</guid>
    </item>
    <item>
      <title>MARINE PROPULSION: OWNERS VIEW 1980'S WITH CAUTION</title>
      <link>https://trid.trb.org/View/159846</link>
      <description><![CDATA[The article is based on interviews with shipowner's superintendents and deals with the following topics: Changes in engine room design and layout.  Development of more economical power plants.  Combustion of future fuels.  Fuel blending.  Alternative fuels.  Repower from steam to diesel. Burning heavy fuel in medium-speed diesel engines. Integrated power plants.  Selection of propulsion machinery. Propulsion machinery suitable for operation on future fuels. Order from NSFI as No. 19841.]]></description>
      <pubDate>Wed, 08 Oct 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/159846</guid>
    </item>
    <item>
      <title>THE FUEL CONSUMPTION OF MEDIUM SPEED ENGINES: AN ANALYSIS BY MAK</title>
      <link>https://trid.trb.org/View/154863</link>
      <description><![CDATA[Factors to be considerd by shipowners and yards when comparing the fuel consumption figures claimed for various medium speed four-stroke engines are examined by a leading company in this sector, stressing the importance of evaluating the consumption of the complete engine installation.  Topics discussed include: Combustion quality; Cycle efficiency/thermal losses; Mechanical efficiency and Auxiliary power plants; Charge variation, efficiency of supercharging processes; and Maintenance of optimum condition in operation.]]></description>
      <pubDate>Wed, 08 Oct 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/154863</guid>
    </item>
    <item>
      <title>THE ADAPTABLE DIESEL ENGINE-NEW DEVELOPMENTS AIMING AT MAXIMUM FUEL ECONOMY</title>
      <link>https://trid.trb.org/View/152240</link>
      <description><![CDATA[The fuel shortage and the coincidental deterioration in fuel quality call for adaptable engines.  Their economy should be very high over as broad a load range as possible.  Moreover the engines should be optimally adaptable to the specific ambient conditions.  As the new fuels have in part widely varying combustion characteristics the injection system itself must also be easily adjustable.  Many engines are operated predominantly in the part load range.  This must also be taken into account when designing the engine.  The substantially differing types of propulsion in ships, as also in stationary applications, require a widely varied programme.]]></description>
      <pubDate>Tue, 16 Sep 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/152240</guid>
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    <item>
      <title>INTEGRATED SHIP MACHINERY SYSTEMS WHICH RESULT IN SMALL, EFFICIENT DESTROYERS</title>
      <link>https://trid.trb.org/View/154057</link>
      <description><![CDATA[The use of properly selected integrated ship machinery systems can sharply reduce the size, installed power, and fuel consumption of future Destroyers without reducing payload, speed, range, margins, or stability.  One properly chosen subsystem opens the way to using a second superior subsystem, thus a third one, et cetra, forming a sort of beneficient chain reaction.  The superior subsystems themselves provide highly leveraged effects on the displacement of the ship.  Synergism of this entire chain can result in ships with markedly reduced initial and operating costs.  The most essential elements of this system are: aircraft derivative gas turbines; compact, lightweight electric transmissions; large battery energy storage systems; and contrarotating propellers.  Adoption of these systems permit secondary high-leverage subsystems to be used, including efficient ship service power from propulsion turbines and light-weight maintainable propulsion pods. These changes make total ship rearrangement possible, resulting in major decreases in turbine ducting, propulsion shafting, electric power distribution, and propulsion auxiliaries.  Similar benefits in the auxiliary machinery system result from adoption of reverse-osmosis fresh water production, heat pumps for space heating, glass-reinforced plastic piping, controllable-speed, high-efficiency pump motors, et cetera.]]></description>
      <pubDate>Thu, 26 Jun 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/154057</guid>
    </item>
    <item>
      <title>AN EVALUATION OF ENERGY CONSERVATION APPROACHES FOR SURFACE SHIPS</title>
      <link>https://trid.trb.org/View/154055</link>
      <description><![CDATA[Lower Fleet operating costs and independence from foreign fossil fuel resources are the goals of energy conservation efforts for Navy surface ships.  This paper describes an evaluation of a wide variety of energy conservation approaches.  A standard 20-knot, 300-hour Destroyer mission is established so that all of the approaches can be compared on a total fuel required basis.  The approaches studied include use of aluminum hull construction; light weight machinery; tail-shaft or cross-connect operation for twin screw ships; improved performance propulsors; advanced power plant types, such as COGAS or cruise engines; use of energy storage techniques to improve ship service generator performance; electrical load reductions; improved performance ship service generators; hull drag reductions; crew size reductions; design margin reduction; reduced performance requirement (such as top speed);  and habitability standard reductions.  The overall results can be effected by reductions in range requirements as well. Mission duration was held constant at 45 days throughout the study.  The results of the study indicate that the combination of these various possible improvements may reduce the fuel used to be as low as one-third of the current levels.  Weight reductions are very effective for achieving significant fuel savings.]]></description>
      <pubDate>Thu, 26 Jun 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/154055</guid>
    </item>
    <item>
      <title>THE V.A.P. TURBINE MACHINERY</title>
      <link>https://trid.trb.org/View/153395</link>
      <description><![CDATA[The VAP propulsion system is a complete steam turbine machinery concept including boiler, fluid bed superheater/reheater, main propulsion unit, feed water heaters, pumps and other auxiliaries.  It has been designed by Stal-Laval to improve the competitive potential of steam propulsion.  The design philosophy is described with its two main objectives which retain the traditional well known qualities of the steam turbine propulsion system: high availability, low maintenance cost and small installation volume with an improved and competitive fuel economy.  The VAP system introduces a number of new technologies such as: 1) Fluid bed combustion; 2) Nickel-base alloys for super-heater and turbines; 3) High speed HP-and IP-turbines; 4) Compact planetary gears (CPG).  In this paper only the main propulsion unit is described in detail.  The paper ends with a discussion about the potential of the VAP concept for further development, and it is concluded that the new technologies introduced with the VAP system are used in a very cautious way with very high safety margins built into the system.  This means that there will be room for considerable further progress when the first experience has been gained from the VAP system, which is defined as "a beginning of the road technology."]]></description>
      <pubDate>Wed, 07 May 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/153395</guid>
    </item>
    <item>
      <title>MARINE BOILERS FOR VERY ADVANCED PURPOSES</title>
      <link>https://trid.trb.org/View/153390</link>
      <description><![CDATA[The Paper Considers the problems facing marine steam generation today.  Comparing the situation with that existing some 15 years ago will show the current basis for further development to be sound.  A statement of the basic problems are made and solutions to them considered in some detail.  The use of Reheat and advanced steam conditions as they affect boiler design are examined and the development of designs up to the limits of current technology are reveiwed.  Prominence is also given to a new method of combustion involving the use of fluidized beds.  This new technique is seen in relation to Very Advanced Propulsion Plant new being actively developed and the means are considered whereby it will allow the removal of former barriers to improved economy of operation.  Current and future plans for the exploitation of the principles involved will be indicated.  The Very Advanced Purposes mentioned in the title are not meant to imply standards of operation and supervision which have left current capabilities far behind, but more an acceptance of the fact that propulsion plant now being developed is far in advance of that in current use in terms of overall efficiency.  That this can be achieved without deterioration in availability may require the acceptance of a package approach to the selection of important components.]]></description>
      <pubDate>Wed, 07 May 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/153390</guid>
    </item>
    <item>
      <title>THE DESIGN OF HIGH POWER SHIP PROPULSION GEARING WITH HYDRODYNAMIC COUPLINGS</title>
      <link>https://trid.trb.org/View/153360</link>
      <description><![CDATA[The Vulcan coupling, which AG Weser has been using in association with Diesel engine gearing for many years, has contributed greatly to the successful application of the medium-speed engine for ship propulsion.  After mentioning some examples of the application of the Vulcan coupling in high-power multi-engine installations, the Author lists the advantages of this coupling, and describes its method of operation (it works on the Fottinger principle) and its design and construction.  For ships that operate in ice (or in other difficult conditions), this fluid coupling can be equipped with a slipping arrangement that allows the engine to develop maximum torque at the most favourable rpm while the propeller operates at the corresponding torque and reduced rpm.  A device can be added to ensure rapid uncoupling (by emptying the coupling within one second) if the propeller should become blocked by ice.  These arrangements are briefly described.  Order from BSRA as No. 52,322.]]></description>
      <pubDate>Wed, 07 May 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/153360</guid>
    </item>
    <item>
      <title>TURBINES AND GEARS FOR MODERN SHIP PROPULSION SYSTEMS</title>
      <link>https://trid.trb.org/View/153394</link>
      <description><![CDATA[To meet the needs of current and projected shipbuilding activity, General Electric launched a new design program, designated as MST-21, which incorporates in the low power steam propulsion machinery (9,000 to 19,000 shaft horsepower) advances made in the higher-powered units in recent years -- higher steam conditions, more efficient nozzle and bucket construction and improved throttle controls to interface with the unmanned engine room.  Reheat as well as non-reheat turbine designs are part of the MST-21 program.  New reheat turbine frames are being made available suited to lower-powered applications.  Also, included in the MST-21 line of turbines and gears are a number of design options which can, in various applications and for certain ship operating profiles, provide important economic gains. These options include attached auxiliaries, thermal-coupled units for twin screw drive (with either "fixed pitch" or "controllable and reversible pitch" propellers) and improved part load performance.  Condition monitoring has come to the fore as a way of insuring that mechanical reliability and thermal efficiency will be maintained over the life of the equipment.  Provisions are made in the design of the propulsion machinery to facilitate both continuous and periodic observations and an owner service can be provided to evaluate the machinery condition based on these observations.  In response to a strong interest in the marketplace in very high thermal efficiency, there has been a general upgrading of the entire non-reheat and reheat families of turbine frames coincident with the MST-21 program.  Noteworthy, in this effort is the new reheat turbine design developed under contract to the U.S. Maritime Administration which operates at steam conditions of 165 bars and 566 degrees C and makes possible an all-purpose fuel rate of 165.5 grams per metric shaft horsepower-hour.]]></description>
      <pubDate>Wed, 07 May 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/153394</guid>
    </item>
    <item>
      <title>ON THE PROPULSION QUALITY OF SHIPS OPERATING AT RESTRICTED WATER DEPTH</title>
      <link>https://trid.trb.org/View/153351</link>
      <description><![CDATA[For a ship of fixed speed in a fixed depth of water, the most economical propulsion is that for which a minimum of propulsive power is required.  The inverse power-displacement coefficient is then a maximum, and propulsive efficiency is of minor importance.  However, even the inverse power-displacement coefficient is not very appropriate for checking the propulsive quality, for up to now no upper limits for this coefficient that are suitable for realistic optimisation procedures have been defined. The propulsive power for a given hydrodynamic ship-design as obtained, for example, in model tests can be checked by means of a reference power.  This reference power is a function of significant parameters of the hull, propeller, and flow.  To define an efficiency, the reference power should be the lowest possible power in a physical realistic meaning.  The Author explains in detail the derivation of suitable reference powers, and shows how they can be used to represent the total efficiency of ship propulsion at a restricted water-depth.  The foregoing considerations are then applied to two cargo-ships, one single-screw and the other twin-screw, designed for operation on the Danube and for which model-test results are available.  The propeller efficiency and propulsive efficiency of the two ships are discussed, and several conclusions are drawn; it is mentioned that, owing to lack of information from river-going ships, no further conclusions should be drawn at present.  Some optimum propulsion data for sea-going ships are included to indicate propulsion quality when restraints applying to river-going ships are omitted from consideration.]]></description>
      <pubDate>Wed, 07 May 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/153351</guid>
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