bluuebunny/crossref_metadata_2025_split huggingface dataset:
Titanium Cooling Coils for Surface Ship Applications
Authors: BROWN DAVID A. , BAE YOUNG L. 
Published: March 2009

ABSTRACTHigh machinery space temperatures and generally inadequate ventilation air cooling in many Navy ship machinery compartments influenced a David Taylor Research Center (DTRC) decision to reevaluate seawater cooling coils as a principal means of compartment cooling. Earlier Navy designed and fabricated copper‐nickel seawater coils had suffered numerous reliability problems due to fouling, corrosion, and erosion and, thus, were removed from ship use.Advanced plate‐fin and integral fin cooling coil designs were evaluated as a means of improving reliability and thermal performance of the previous Navy seawater cooling coils. Math models were developed to analyze the effects of (1) seawater and air temperature, (2) seawater and air flow rates, and (3) coil material on thermal performance. Unique fabrication techniques were assessed for both coils to allow fabrication using titanium in place of copper‐nickel for all seawater‐wetted components. Finally, various cooling coil waterbox de signs were evaluated to improve the seawater flow patterns and thus reduce fouling and increase component reliability.Results showed that both cooling coil designs can satisfactorily handle cooling requirements of machinery spaces on existing and future class ships without the need for large increases in air conditioning capacity. Furthermore, both seawater coil designs can be fabricated from titanium by modifying fabrication techniques used in the previous design.The recommended general design approach, as concluded from the study, can be summarized as follows:

Increase air velocity across the coil to maximize thermal performance;
Increase seawater flow rate in the tubes and water‐box to prevent biofouling accumulation;
Limit the compartment ventilation air to only that amount needed for life support;
Provide a small chilled water coil in the compartment for latent heat removal and;
Utilize titanium as the seawater‐wetted component material to increase reliability over the copper‐nickel coil previously used.
Circuit Breaker Shock Testing ‐ Individual Component Tests and Apparatus Mounted Tests
Authors: BURDETTE ARTHUR W. , DAVES TED M. , YKEMA JOHN I. 
Published: March 2009

ABSTRACTThe integrity of circuit breakers in a shock environment is essential to the survivability of naval combatant ships. A momentary disruption of power due to the opening of circuit breakers can disable essential combat systems equipment for a substantial period of time relative to the required response time of these systems. Even with the ongoing effort to provide shock hardened circuit breakers, the record indicates that shock integrity has been a continuing area of concern during ship shock trials.An historical review is provided of the efforts which have been undertaken to improve the shock resistance characteristics of circuit breakers and of the circuit breaker mounting structures (i.e., in switchboards or panelboards).Circuit breakers have exhibited varying shock resistance characteristics when tested individually versus when tested as an integral member of a switchboard or panelboard, therefore, a comparison is provided of the shock testing specification requirements of circuit breakers tested as components and of the assemblies into which they are commonly mounted. The differences are analyzed to postulate possible causes for the inconsistency of shock qualified circuit breakers when shock tested in their operating environment.An analysis is provided of the similarities and differences of shock impacts on circuit breakers when tested as components and when tested in a switchgear or panelboard assembly. Two series of tests were conducted, one involving circuit breakers in a panelboard and the other involving circuit breakers in a switchboard. The analysis compares the acceleration‐time histories, velocity, displacements, and the shock spectrum derived therefrom. Of particular interest is the mounting structure of circuit breakers when shock tested as components and the interaction of the switchboard structure with the circuit breakers under shock impacts.Recommendations are provided for improvements in specifications, for improvements in the design of the assemblies which house the circuit breakers, for improvements in circuit breakers and for more stringent requirements regarding first article testing of assemblies.
Computer Aided Design Methods for Propeller Fillet Gages
Authors: ALLEN DAVID W. , VINOSKI WALTER S. , OVERTON BERNARD A. 
Published: March 2009

ABSTRACTOne of the most complicated forms encountered in engineering design is that of the marine propeller. The complexities arise from the complicated hydrodynamic surfaces of the propeller blades and the complicated manner in which the blades are oriented with and attached to the hub. Where propeller blades are attached to the hub, the blade shape is blended into the shape of the hub. The geometry of this region is particularly complicated. The shape of the blend is called a fillet, and the blending region is called the fillet region.Sheet metal gages conforming to various blade surface contours are used in the manufacture and inspection of propellers. Five different types of gages define the shape of the propeller in different regions. Fillet gages are such gages that define the shape of propeller blades in the fillet region.This paper describes a new computer‐aided method for designing fillet gages. Previous methods of fillet gage design required the designer to follow a complicated layout procedure of determining where a particular unfilleted blade contour intersected the hub. The design of the fillet was then done in another layout procedure. Newly developed numerical procedures incorporated in a computer program have reduced the time required to design a complete set of gages (including fillet gages) from up to several weeks to hours.
A System Engineering Approach to Surface Combatant Design Issues
Authors: RAINS DEAN A. 
Published: March 2009

ABSTRACTThe design of naval surface combatants presents a challenging system engineering problem. There are many important choices to be analyzed and made. Within the limitation of the available technologies, there are many design decisions to be made even if no new technologies are selected. The purpose of this paper is to explore ship design optimization in a system engineering context. The design issues to be considered are ship speed, combined with powerplant size selection, endurance, and level of passive survivability. These issues are addressed from a design viewpoint using current technologies. It will be left to future efforts to explore the merits of new technologies. Military effectiveness and affordability analyses are used to determine the best selection of design parameters for future combatants. The analysis procedures used, together with the results, are summarized for reference and use.
New Developments in Butterfly Valves
Authors: BHASIN VINOD , NILSEN LLOYD 
Published: March 2009

ABSTRACTButterfly valves are made with distinct features and end‐to‐end dimensions, meeting several industry standards. They can be broadly classified as: rubber‐seated and high‐performance (HPBV) butterfly valves. The rubber‐seated valves are well suited for on/off applications at lower operating pressures and are very economical, however the HPBVs offer chemical inertness and superior performance at higher pressures and temperatures. Like other types of valves, butterfly valves have certain drawbacks, and not all of them are properly designed. However, in many applications in the fleet, which have required traditional gate, globe and rubber‐seated butterfly valves in the past, HPBVs offer improved performance and substantial economies when a well‐designed HPBV with the desired features is selected and installed with due considerations.
Future Naval Contingency and Limited War Operations
Authors: Pace Dale K. 
Published: March 2009

ABSTRACTThe world has changed dramatically in the past few years. In large part, many of the changes have been driven by the emphasis now given to contingency and limited war operations. Navy leadership even coined a special term for them late in the 1980s: CALOW (Contingency and Limited Objective Warfare). As a result, naval planning has also changed, and with it so have the demands upon naval engineering. This paper addresses some of the factors that are now shaping naval planning. Characteristics of contingency and limited war operations are presented. Their implications for naval planning, for naval systems, for concepts of employment, and for naval force structure are examined. It is important that both Navy leadership and the naval engineering community understand these implications fully so that they may respond to them appropriately. The specific value of this paper lies in its synthesis of information so that the naval engineering community may appreciate the full impact of future contingency and limited war operations.
Small Ships, Advanced Technology and Warfighting Performance
Authors: SKOLNICK DAVID H. , SKOLNICK ALFRED 
Published: March 2009

ABSTRACTChanging threat requirements and radical budget shifts imply that Navy operational needs will broaden and engineering solutions will face tougher constraints. Existing and emerging technology promise increased combat capability in smaller packages; space‐based assets will allow operator orchestration of widely dispersed naval units via connectivity attributes previously unavailable. Tactical data relay by downlink may permit reallocation of responsibilities among several platforms, space, air, or seaborne, so ships can be outfitted for custom‐use (sensing, unique data processing, high‐firepower) and optimized to meet specific mission needs. These evolving capabilities demand a fresh look at ship concepts and prospective force structures consistent with global and fiscal realities. Warfighting performance formerly unknown in small ship design may offer a very effective solution to the intricate, interacting issues of falling defense budgets, diverse operational requirements and complex national priorities. Multimission ships which take advantage of new or current technology to reduce ship size, manning and cost could be affordable in sufficient numbers to meet our continuing worldwide obligations, complement our larger ships' force structure, and produce a balanced fleet. These same ships could satisfy U.S. maritime needs beyond the Navy and improve export trade through foreign military sales (FMS).
The Navy's Chlorofluorocarbon/Halon Program
Authors: KRINSKY JOEL L. , NOEL WILLIAM 
Published: March 2009

ABSTRACTThe Naval Sea Systems Command is executing a three‐phase program to ensure compliance with national regulations, DoD policy, and Navy instructions mandating the phase‐out of CFC and Halon use by the Navy. The Navy uses significant quantities of CFCs and Halon as solvents, refrigerants, and fire‐fighting agents both in military operations and through specifications and contracts for weapons and support equipment.Phase one of the program plan will be to conserve chemicals through reclaiming and recycling, and by establishing and maintaining a chemical inventory of CFCs and Halons. Phase two will research, develop, and test substitute chemicals and alternative technologies for existing CFC uses. This research will be pursued through Navy and government laboratories, cooperation with chemical and equipment manufacturers, and by participation in government/industry consortiums. Finally, phase three will deploy the replacement chemicals and new technologies into the fleet, and institutionalize the conservation measures developed in phase one.This paper discusses in detail the three phases of the Navy program, and relates the Navy effort to DoD policy, the Montreal Protocol, and Congressional legislation. Unique Navy concerns, research initiatives, and vintaging scenarios for existing equipment are presented.
A Computational Study of HY and HSLA Steel Performance in a Bulkhead Test Panel Geometry
Authors: DEGIORGI VIRGINIA , MATIC PETER 
Published: March 2009

ABSTRACTAs nonlinear computational methods become integrated into the structural design and analysis process, the effects of large deformation material response on large deflection structural response can, in principle, be predicted. The accuracy of structural predictions ultimately depends on an accurate assessment of the material responses which are encountered in the structure. This is particularly true if information on locally severe plastic deformation or fracture initiation and flaw tolerance is desired.Previously determined parameters for the elastic‐plastic response of HY‐80, HY‐100, HSLA‐80 and HSLA‐100 steels, accurate through large strains terminating at the point of fracture, were applied in finite element simulations to predict the performance of a bulkhead test panel geometry. Significant differences in panel performance under hydrostatic loading conditions were predicted for the materials considered. The plastic deflections were found to be strongly influenced by the relative local or diffuse nature of intense plastic deformation across the panel. These results suggest that the comparative nonlinearity of these materials was as important as the strength and ductility in affecting performance. Further analyses, aimed at assessing flaw tolerance, were considered by conducting small scale analyses of local details where severe deformation conditions were predicted by the larger scale panel model.
An Overview of Current and Candidate Titanium Alloy Applications on U.S. Navy Surface Ships
Authors: SCHUTZ RONALD W. , SCATURRO MILTON R. 
Published: March 2009

ABSTRACTA significant number of current and candidate Navy surface ship applications for titanium alloys are identified and reviewed in this paper. These applications represent very viable, practical engineering solutions to current limitations and problems on current ships, and improvements proposed to address modern Navy aims. These fundamental aims include improved ship performance, availability, payload, mobility, and survivability. A thorough discussion of relevant mechanical, physical, and corrosion properties of candidate titanium alloys is made along with how these properties Impact design, fabricability, and performance of specific ship structures and systems. An update of the status of these ship applications and corresponding Navy evaluation programs is also provided.
Structural Analysis Methods for Lightweight Metallic Corrugated Core Sandwich Panels Subjected to Blast Loads
Authors: WIERNICKI CHRISTOPHER J. , LIEM FRANZ , WOODS GREGORY D. , FURIO ANTHONY J. 
Published: March 2009

ABSTRACTSince the early 1980s, the U.S. Navy, in conjunction with industry, has continued to develop and test innovative lightweight structural concepts with the purpose of seeking alternative replacements for conventional plate beam metallic structures. One commercially available concept currently under investigation is lightweight metallic corrugated core sandwich panels. This paper presents both elastic and plastic design methods for lightweight metallic corrugated core sandwich panels subjected to air blast loading. The equations presented in this paper, while not a complete solution to the complicated dynamic, elastic plastic phenomena of blast wave‐rigid body interaction, are offered as a set of relatively simple analytical expressions that can be used in preliminary design. Because of the closed form nature of the equations the designer has the capability to quickly identify the most important parameters effecting the response of lightweight metallic corrugated core sandwich panels to air blast loads.
Concept for a Force Level Combat System
Authors: YOUNG M. BRIDGET 
Published: March 2009

ABSTRACTThe concept of a superset is not unknown to the Navy. The term “superset” has been applied to the combat systems onboard the Aegis cruisers (CG‐65 through CG‐73) and the Aegis destroyers (DDG‐51 through DDG‐64). David Taylor Research Center (DTRC) has developed several concepts for ship designs which can be considered supersets. The goal of this paper is to develop the concept of a combat system superset, a derivative of which would be deployed on all surface combatants. This combat system superset will contain all warfare area missions and supporting functional elements. The combat system superset should be related to future ship designs to create an integrated surface combatant. The ultimate utility of a combat system superset design would be lower life cycle costs for its derivatives. A notional combat system superset is presented along with three proposed derivatives. The paper concludes with the application of the superset for each derivative and a discussion of the resulting combat systems.
An Affordable Approach for Quality‐Assured Shipboard Maintenance Information
Authors: KNACHEL ROBERT E. , MAGROGAN WILLIAM F. 
Published: March 2009

ABSTRACTAcquisition and logistics professionals recognize the challenges in synchronizing maintenance and supply support information over the life cycle of shipboard systems and equipment. Decisions and judgments made during full‐scale development, then described in maintenance documents and allowance lists, may become outdated for any number of reasons once the ship deploys. Thus, the fleet faces the possibility of out‐of‐sync maintenance support information at virtually any time.Initiatives during the 1980s which reconcile shipboard maintenance and support data include Integrated Logistics Overhauls (ILOs) and Ships Configuration and Logistics Support Information System (SCLSIS). These initiatives aim to ensure all shipboard equipments have current maintenance documents and up‐to‐date allowance lists, but they are expensive, time consuming, and scheduled every 4 to 5 years. Shipboard officers care about today's problem, particularly the next deployment. ILO and SCLSIS products are not always timed to the next deployment, nor is it practical or cost‐effective to do so.Adopting the perspective of shipboard maintenance and supply officers, the authors identify three fundamental maintenance support information needs which quality assure readiness to perform a ship's mission:Technically complete, accurate, and up‐to‐date maintenance documents for all mission critical equipments.One‐to‐one correlation between authorized maintenance parts required and authorized allowance/ordering data for mission critical equipments.Assurances that all allowed mission critical parts needed for shipboard maintenance are on board or will be delivered prior to deployment.The authors maintain that the most affordable solution to shipboard maintenance support information quality assurance is to select mission critical equipments with significant CasRep or shipboard “trouble” histories and resolve any maintenance support information discrepancies prior to deployment “real‐time.” This approach supplements, but does not replace, the ILO and SCLSIS processes. This approach was designed using total quality management principles to assure mission effectiveness.
Tooling for Impeller Castings Via CAD/CAM
Authors: MEYER ERICH A. 
Published: March 2009

ABSTRACTThe tooling required to make 20‐inch‐diameter impeller investment castings for shipboard centrifugal pumps is NC machined directly from a CAD/CAM computer database without the use of pattern drawings. A Computervision CADDS 4 system, in conjunction with a 3‐dimensional coordinate measuring machine, form a Computer Aided Design (CAD)/Computer Aided Inspection (CAI) System used to design, inspect, and manufacture the impellers. The impeller design data is transferred to a second CAD system used for machining the impeller master core and final production tooling. The CAD impeller models are fully surfaced 3‐dimensional representations of the designed and manufactured vane surfaces. Inspection results indicate minimal deviation between the manufactured vane surfaces and design specifications. Similar CAI system inspections of hand made wooden masters from pattern drawings have proven that 60% of the tooling for impeller and casing vanes have significant deviations from the design specifications which are then corrected before the pattern is approved. The tooling cost is competitive with conventional pattern tooling costs for this type of contract and size of impeller. The tooling lead times were about 25% longer than conventional methods of manufacture due to a learning curve effect on the part of the mold shop and the fact that the tooling was somewhat oversize for the available milling machine, necessitating frequent set up changes. Tooling delivery time can be improved as more experience is gained with this method of manufacture.
The Navy's New Standard Digital Signal Processor: The AN/UYS‐2
Authors: RICE MICHAEL L. 
Published: March 2009

ABSTRACTAn architectural summary of the AN/UYS‐2 multi‐processor digital signal processor is presented along with a brief description of the major technologies that are being incorporated into it. Discussion concentrates on the AN/UYS‐2's implementation of data‐flow parallel processing to achieve exceptionally high computing throughput rates. In addition, its functional components and the implementation of its hardware functional elements into standard electronic modules are discussed. Supporting this multi‐processor architecture is a signal processing graph language methodology called Processing Graph Methodology (PGM) which is used to efficiently and cost‐effectively program the AN/UYS‐2. Finally, follow‐on candidate technologies for infusion into the AN/UYS‐2 are highlighted.
Surface Effect Ship (SES) Developments Worldwide
Authors: LAVIS DAVID R. , SPAULDING KENNETH B. 
Published: March 2009

ABSTRACTIt has been more than 30 years since the introduction of the SES. There are several hundred operating SES in the world today. Most are relatively small (less than 200 tons) and have operating speeds of 25 to 40 knots. The potential for larger, faster, SES has long been recognized. Today, with the emergence of six independent European initiatives for the development of 40 to 50‐knot, 500 to 2000‐ton, SES car ferries, we are on the threshold of a new generation of SES (Figure 1) — which will be introduced solely because they are perceived, by hard‐headed investors, as competitive commercial ventures.In this paper the history of SES development is summarized and a world‐wide census of SES craft presented. Current fast‐ferry and military initiatives are discussed. The SES concept is defined and characterized including a discussion of SES technologies. Predictions are made regarding future SES developments, followed by conclusions and recommendations.
Ready Reserve Fleet Activations: The View from the Deckplates
Authors: OTT ANDREW A. 
Published: March 2009

ABSTRACTThe 2 August 1990 Iraqi invasion of Kuwait and its subsequent political developments quickly led to the recognition that a “military solution” was at least a possibility. To support the large military logistics effort that would obviously be required, a mass activation of the nation's Ready Reserve Force commenced on 9 August 1990. By early 1991, over seventy ships had been designated for activation. This enormous effort severely strained the resources of the Ready Reserve program, as well as the commercial ship repair industry in the United States. It also overloaded the already limited resource pool of available mariners to man the ships. Although several foreign charters were initially necessary to meet the demand, within a short time the availability of successfully activated U. S. reserve fleet ships grew to fill the wartime need. This article reviews the National Defense Reserve Fleet (NDRF) and the current posture of the Ready Reserve Force (RRF) activation program, provides several firsthand examples of how activations are played out on the deckplates, and presents a summary of lessons learned; all in search of improvements which might make the process even more successful when the RRF is needed again in the future.