This paper reports on an investigation of the applicability of recent hull efficiency improvement concepts to U.S. Navy ships. Among the concepts investigated were stern flaps, Grim Wheels, alternate aftbody configura...
详细信息
This paper reports on an investigation of the applicability of recent hull efficiency improvement concepts to U.S. Navy ships. Among the concepts investigated were stern flaps, Grim Wheels, alternate aftbody configurations, bulbous bows, and flow modifying ducts. Extensive model testing was conducted at the David Taylor Research Center (DTRC) for each concept, and care was taken to check out critical propeller cavitation and noise aspects associated with the investigation of alternate stern configurations and Grim Wheel concepts. A guiding principle in this program was to utilize the expertise available both here and abroad so that each design concept would have the greatest chance of success. As a result of these investigations, significant gains in fuel economy were obtained. Specifically, full scale trials of FFG-25 (USS Copeland), equipped with and without a stern flap, demonstrated that fuel savings of 5-9% are achieved at speeds above 12 knots. In addition, fuel savings of 9.4% for T-AGS 39 equipped with a Grim Wheel and 5.6% for the combination of a large bulbous bow and a large diameter/low RPM propeller on AE-36 have been predicted. The paper concludes with a direction for future applications to U.S. Navy, and other ships.
This paper outlines the essential features of a recommended engineering approach to load and motion determination, required developments, progress to date and remaining key developments. An engineering approach is def...
详细信息
This paper outlines the essential features of a recommended engineering approach to load and motion determination, required developments, progress to date and remaining key developments. An engineering approach is defined as one in which all significant cause and effect relationships have been identified and quantified so that the resulting design criteria and methods can play a deterministic role in the give and take of ship design. In defining the essential features of such an approach consideration is given to (a) the random nature of the seaway, (b) linear and nonlinear characteristics of the seaway and ship responses to it, and (c) the use of resulting loads and stresses in the assessment of as-built static strength, fatigue and flaw growth degradation of static strength, and energy absorption under seaway impact loadings. Progress to date in these areas is overviewed and recent developments summarized which serve to demonstrate that the rather demanding elements of an engineering approach are attainable. Because of the importance of seaway characteristics, primary attention has been given to providing an effective engineering definition of world wide wave climates. In addition, because of the importance of nonlinear seaways and ship responses, a method of characterizing the nonlinearity of measured random data has been developed. With these advances in hand, remaining critical developments are identified and approaches to their resolution suggested.
作者:
CERMINARA, JKOTACKA, ROJohn Cerminara:is a principal engineer with Westinghouse Machinery Technology Division
Electrical Systems Department. He holds a B.S. degree in electrical engineering from the University of Pittsburgh. He is a registered professional engineer and a member of IEEE ASNE and the Ship Steering Group of the Combat Survivability Division of ADPA. Mr. Cerminara has had over 30 years of multidiscipline experience ranging from engineering and construction in heavy industry to standards and publications. Past assignments include DOE/ NASA wind turbine project manager for Westinghouse and task leader of MTD electrical systems. Most recent assignments have included hull mechanical and electrical (HM&E) distributive system survivability analyses of the LSD-41 mobility mission area and application and validation of NavSea computer-aided design of Survivable Distributive System (CADSDiS) Program. Rolf O. Kotacka:is presently a ship systems engineer in the Ship Systems Engineering Branch of the Naval Sea Systems Command Engineering Directorate
where his primary responsibility is ship system survivability. He is a 1977 graduate of SUNY Maritime College where he received his bachelor of engineering degree in marine electrical engineering as well as a U.S. Coast Guard Third Assistant Engineer License and a commission in the U. S. Naval Reserve. Upon graduation Mr. Kotacka was employed by Charleston Naval Shipyard as a field engineer until 1981 where he gained his background in surface ship HM&E systems and equipment. He then transferred to the Supervisor of Shipbuilding Conversion and Repair Groton where he served as a senior electrical engineer monitoring the design and construction of Trident and 688 class submarines and received the Meritorious Unit Citation. Prior to his present position Mr. Kotacka was the life cycle manager for diesel generator sets in the Naval Sea Systems Command's Generators Branch. He has coauthored several papers dealing with power generation for ASE and SNAME. Mr. Kotacka is also a lieutena
This paper highlights the survivability concerns in the design of ship service power systems. The paper gives a brief description of what constitutes a typical ship service electric power system and concentrates on el...
详细信息
This paper highlights the survivability concerns in the design of ship service power systems. The paper gives a brief description of what constitutes a typical ship service electric power system and concentrates on electric power generation and associated controls. Established survivability design principles and guidelines are highlighted and the application of those guidelines are discussed. General Specifications (Gen Specs) for Ships of the U.S. Navy are cited as the cornerstone for design. Specific design criteria are cited as well as the rationale associated with the survivability design guidelines pertaining to power generation and distribution. The application of these survivability design guidelines plus the use of the deactivation diagram/damage tolerance analysis cited in the Gen Spec section 072e will enhance overall design and help ensure survivable electric power systems for surface combatants.
作者:
CHENG, BHDEAN, JSMILLER, RWCAVE, WLBill H. Cheng:is a physical scientist in the Numerical Fluid Dynamics Branch
Computation Mathematics and Logistics Department David Taylor Research Center (DTRC) Bethesda MD. Since joining DTRC in 1981 he has been the project leader for the XYZ Free Surface (XYZFS) Program. He received a B.S. in mechanical engineering from the National Taiwan University and a M.A.Sc. in mechanical engineering from the University of British Columbia and a S.M. degree in oceanography and meteorology from Harvard University. Mr. Cheng is a registered professional engineer in the Commonwealth of Virginia and a member of American Society of Mechanical Engineers and Sigma Xi. His experience in fluid dynamics has included theory experiments and computations. He has been the author and coauthor of numerous technical reports and papers. Janet S. Dean:is a mathematician in the Numerical Fluid Dynamics Branch
DTRC. She attended the College of William and Mary and received her B.S. degree in mathematics from The George Washington University. Mrs. Dean assisted Charles Dawson in the development of the original XYZFS Program. She has worked on improving and extending the capabilities of XYZFS and on the application of supercomputers to fluid dynamics problems. Ronald W. Miller:is a mechanical engineer in the Numerical Fluid Dynamics Branch
DTRC. He received his B.A. degree in mathematics from the University of Maryland—Baltimore County Campus in 1984 and his M.S. in ocean and marine engineering from The George Washington University in 1988. Mr. Miller is responsible for the preparation of hull geometry data used in ship hydrodynamic analysis computer codes and the graphical visualization of output from such codes. William L. Cave III:graduated from Stevens Institute of Technology in 1986 with a B.E. degree in ocean engineering. He is currently a naval architect in the Design Evaluation Branch
Ship Hydromechanics Department DTRC. He has been involved with model testing and evaluation of the CV-41 FFG-7 class USNSHayesCG-47 class
A computational capability has been developed to predict and visualize the flow about podded propulsors appended to the 154-foot transom stern research vessel, R/V Athena . The computer generation of a complex geometr...
详细信息
A computational capability has been developed to predict and visualize the flow about podded propulsors appended to the 154-foot transom stern research vessel, R/V Athena . The computer generation of a complex geometric model for the hull and appendages is an important part of this new capability. The flow field is computed using a free surface potential flow method. The steady flow induced by the propulsor is simulated by an idealized propeller model (actuator disk). The upstream effects of an actuator disk are examined and results are compared to the case without an actuator disk. Computed results for the inflow to the propeller disk are presented as velocity vector plots and contour plots. Harmonic analyses are performed on the computed velocity components. The numerical results can be used in conjunction with experiments performed at DTRC to aid in the design of podded propulsors. These flow studies are used to examine the proper alignment of the pod/strut system with the aim of obtaining the optimal flow into the propeller. The combined numerical and experimental approach is shown to be an efficient way to evaluate complex hull forms with podded propulsors. This powerful design approach can be used for future Navy ship designs.
Both the timely manufacture of defense systems and their subsequent on-line operability depend upon the availability of component parts. The growing problem of microelectronic component nonavailability is casting a sh...
详细信息
Both the timely manufacture of defense systems and their subsequent on-line operability depend upon the availability of component parts. The growing problem of microelectronic component nonavailability is casting a shadow over logistics support to these systems. This paper will discuss the causes of the problem and provide some examples of cases confronted by the DoD logistics community. It will also identify some actions which have been taken in the past to manage the issue as well as initiatives now underway. Finally it will look at what lies ahead.
作者:
FUNG, SCThe author is a naval architect with the Preliminary Design Division of the Naval Sea Systems Command. Mr. Fung graduated from National Cheng Kung University in 1976 and Stevens Institute of Technology in 1977
from which he received his B.S. degree in naval architecture and marine engineering and M.S. degree in ocean engineering respectively. He started his career with M. Rosenblatt and Son in 1979 and became a senior naval architect with the Hull Form & Hydrodynamics Department in Designers and Planners in 1981. For the past ten years Mr. Fung has performed a variety of tasks in the area of feasibility study hydrodynamic design including advanced marine vehicles bulbous bows and hull form design for surface combatant and non-combatant ships. Currently he is a project naval architect for the T-AO twin skeg integrated hull design and the AE-36 Energy Enhancement Program. Mr. Fung is a member of ASE ASNE and SNAME. He received the John C. Niedermair A ward in 1984 and 1986 for the best paper presented at the ASE annual technical symposiums.
In this paper 154 auxiliary type monohull designs are analyzed for guidance on how to select the appropriate hull form parameters, particularly with regard to the effects of hull section shapes, sectional area and des...
详细信息
In this paper 154 auxiliary type monohull designs are analyzed for guidance on how to select the appropriate hull form parameters, particularly with regard to the effects of hull section shapes, sectional area and design waterline curves on ship resistance. This paper also discusses the resistance predictions based on (1) the statistical approach and (2) the use of series model test data (such as Taylor's standard series) and associated “worm curve factors” with the help of data management software.
作者:
LARIMER, GMCCOLLUM, JSCHAUB, BVANLIEW, DWHIPPLE, CGary Larimer:received his B.S. (1974) and M.S. (1975) degrees in naval architecture and marine engineering from the University of Michigan. He has worked with the Bechtel Professional Corporation
the David Taylor Naval Ship Research and Development Center and the United States Coast Guard. He is a member of SNAME ASNE ABYC and IMTI. He is the author of “Reaction Fin Applications In Marine Propulsion” which documented the use of asymmetric pre-swirl vanes to increase propulsion efficiency aboard a 41-ft Coast Guard utility boat. It was presented on 5 March 1987 at the Hampton Roads section of SNAME and was nominated for the section paper of the year award. CWO3 Joe Bobby McCollum
USCG: iscurrently engineering officer of the Surface Effect Ship Division Seventh Coast Guard District Key West Florida. Prior to this assignment he was assistant engineering officer on the USCGCUte.His other duty tours included engineering assignments on theCape Currenta 95-foot patrol boat on the USCGCUnimak
a 311-foot cutter CG Loran Station Upolo Point
Hawaii and CG Station Sabine Pass
Texas. CWO McCollum was responsible for modifying and repairing the SESs and contributed many unique problem solving ideas which resulted in much improved operation of the Coast Guard Surface Effect Ship Division. Benton H. Schaub:is a senior engineer with Maritime Dynamics
Inc. He has a bachelor of science degree in naval architecture and marine engineering from the Massachusetts Institute of Technology. Mr. Schaub has fifteen years of experience working as a test engineer project engineer and design engineer on advanced marine vehicle projects and is a recognized authority in the areas of hull structure seal system and machinery design for surface effect ships. He has participated in virtually every USN SES design development and test evaluation program including: XR-5 XR-10 SES-100A SES-100A1 and the SES-200. He is currently responsible for performing detailed design and analysis in support of the seal system for the Germa
During the early 1980s the United States Coast Guard took delivery of three surface effect ships (SES) from Bell Halter, Inc. These 136-ton, 30-knot plus, aluminum hulled cutters were to be used primarily for drug int...
详细信息
During the early 1980s the United States Coast Guard took delivery of three surface effect ships (SES) from Bell Halter, Inc. These 136-ton, 30-knot plus, aluminum hulled cutters were to be used primarily for drug interdiction in the southeastern United States. By early 1985, however, the full load weight of these cutters had grown to 150 long tons, and their top speed had dropped to below 23 knots in calm water. By mid-1985, operation of all three SESs was suspended to prevent possible catastrophic failure of their main engines. At this point, the USCG joined ranks with Textron Marine Systems (then Bell Aerospace), and Detroit Diesel to analyze what had gone wrong, and to propose solutions to the problems encountered. From that beginning, the performance of the Coast Guard's SESs has steadily and dramatically improved until at present all three cutters are able to exceed their original performance specifications. This paper discusses the problems experienced with the SESs, including engine overloading, vibration, ride quality, seal wear, poor lift system performance, and metal cracking, along with the corrective actions taken to solve them. The cooperation between government and private industry, which made this dramatic turn-around in performance possible, is also explored. Lessons learned about SES technology are viewed in relation to the general experience of the Coast Guard with other types of high performance hull forms.
The design of the new 108-ft yard patrol craft (YPs) for the U. S. Naval Academy is described from its beginnings as a senior midshipman design project, through its preliminary and contract design development at the U...
详细信息
The design of the new 108-ft yard patrol craft (YPs) for the U. S. Naval Academy is described from its beginnings as a senior midshipman design project, through its preliminary and contract design development at the U. S. Navy's small craft design team headquarters, Naval Sea Combat Systems engineering Station, Norfolk, Virginia (NAVSEACOMBAT-SYSENGSTA-Norfolk). During preliminary and contract design the Naval Academy Hydromechanics Laboratory (NAHL) provided experimental data to support NAVSEA-COMBATSYSENGSTA-Norfolk's design analyses in powering, seakeeping, and maneuvering. Several tradeoff studies of interest to patrol craft designers are presented. Major events in the detail design and construction of the first boat are described from both the designer's and the shipbuilder's points of view. The launching, builder's and sea trials of the first boat are described.
The design of liquid cargo pumping systems for Navy auxiliary ships can benefit from application of modern commercial tanker practices which have evolved in recent years. Navy auxiliaries, which are outfitted for unde...
详细信息
The design of liquid cargo pumping systems for Navy auxiliary ships can benefit from application of modern commercial tanker practices which have evolved in recent years. Navy auxiliaries, which are outfitted for underway replenishment, traditionally have at least one pumproom and the designs are based upon a conventional pumproom type cargo system with horizontal or vertical centrifugal cargo pumps. Each cargo tank has a dedicated suction line leading to the cargo pumps. Latest commercial product tankers, especially lighters, which most closely resemble Navy auxiliaries in the manner in which they carry liquid cargos, have been built with in-tank deepwell or submersible cargo pumps, thereby eliminating the pump-room. The application of this type of pumping system reduces the size of the ship considerably, thereby resulting in reduction of required propulsive power and fuel consumption as well as a dramatic reduction in construction cost. The three most common pumping system designs are discussed in the paper, together with variations of each. The differences in systems are presented and their effect upon the design of an auxiliary ship is illustrated. The paper investigates the application of these alternate type cargo pumping systems (with dedicated pumps) to the design of a typical Navy auxiliary, indicating the effect upon ship size, weight, volume and power requirements as well as costs. Submersible pumps are compared to deepwell pumps with the advantages and disadvantages of each discussed. Experiences are cited.
作者:
HOPE, JPSTORTZ, VEJan Paul Hope
a native of Northern Virginia received his bachelor of science degree in mechanical engineering from the University of Virginia in 1969. Upon graduation he began his career in the Department of the Navy with the Naval Ship Systems Command in the acquisition of patrol craft mine sweepers and submarine rescue ships. In January 1971 he transferred to the ship arrangements branch of the Naval Ship Engineering Center. He was selected for the long-term training program at George Washington University in 1974 and completed the program in February 1976 with the degree of master of engineering administration. While at the Naval Ship Engineering Center Mr. Hope was general arrangement task leader on the AO-177 CG-47 CSGN CSGN (VSTOL) CGN-9 (Aegis) and CGN-42 and he also assisted in the landmark Naval Sea Systems Command civilian professional community study. In 1978
he was selected as acting head of the damage control section and subsequently was selected as acting head of the surface ship hydrodynamic section. In February 1980 he was promoted to head of the surface combatant arrangements design section. Mr. Hope was selected for the first class of the NA VSEA commander's development program. While on the program he served in the DDGX combat systems engineering division and the DDGX project office of NA VSEA was the assistant director for ship design in the office of the Assistant Secretary of the Navy for shipbuilding and logistics and was the director of weight engineering and the director of systems engineering for the DDG-51 project in NA VSEA. Upon completion of the program Mr. Hope was assigned as the deputy director of the boiler engineering division to create a new division as a major fleet support initiative by NA VSEA. In June 1985 he joined the staff of the Assistant Secretary of the Navy for shipbuilding and logistics. Mr. Hope was presented the Department of the Navy meritorious civilian service medal in June 1983 for his service with the Office of the Assistant Secretary of the
This paper discusses the need and processes for designing warships to meet cost constraints and for managing warship acquisition programs during the design phase to assure effective adherence to production cost constr...
详细信息
This paper discusses the need and processes for designing warships to meet cost constraints and for managing warship acquisition programs during the design phase to assure effective adherence to production cost constraints by the design team. The resource control methodology used during the contract design of the Arleigh Burke class destroyer, DDG-51, is examined as a potential model for controlling the cost while maintaining the combat effectiveness of warships. The paper begins with a summary of the basic issue — the relationship among unit cost, unit capability, force level numbers, and force capability — showing recent trends in destroyer costs and force levels. This introduction also includes a discussion of the cost constraint for the DDG-51 in relation to historical trends and ship construction funding allocation. The resource control methodology used to reduce and control costs of the DDG-51 is discussed with a summary of the approach, key concepts and tools, chronology of key events, examples, and results achieved. A number of observations on this methodology are then made which are followed by comments on life cycle costs. The paper concludes with remarks on the future application of the resource control methodology and areas for further work to improve future resource control efforts.
暂无评论