Francois G Besnier

The 88th Annual Meeting of The Society of Naval Architects and Marine Engineers will convene at The New York Hilton Hotel on November 13-15, 1980 according to an announcement made by Lester Rosenblatt, president of the Society.

"Again this year," Mr. Rosenblatt said, "we will have 14 excellent technical papers on Thursday and Friday . . . . I am looking forward to seeing everyone at the President's Luncheon on Thursday, the Banquet on Friday, and of course, the Saturday night Dinner-Dance." The papers have been especially selected by the Society's Papers Committee for the highest interest to the largest number of people attending, and the final printed papers, discussions and authors' closures will constitute most of the Society's Transactions, to be published in 1981.

Mr. Rosenblatt will give his final message as president at the President's Luncheon in the West Ballroom. Several important awards will be made, among the Cochrane Award and the Joseph H. Linnard Prize, at the Luncheon.

The Annual Business Session will be held at 4:00 p.m. in the Trianon Ballroom, where the members will elect a new president of the Society for a two-year term beginning January 1, 1981.

On Friday at 7:30 p.m., the Annual Banquet will take place in the Grand Ballroom with Mr.

Rosenblatt presiding. After the dinner, the David W. Taylor Medal will be awarded to Peter M.

Palermo, director, Structural Integrity Division, Naval Sea Systems Command. The Vice Admiral "Jerry" Land Medal will be given to P. Takis Veliotis, executive vice president-marine, General Dynamics Corp. and general manager, Electric Boat Division. The biennially awarded Davidson Medal will be presented to Manley St.

Denis, professor emeritus, University of Hawaii. The Elmer A.

Sperry Award will be made to Leslie J. Clark for pioneering work in LNG transport.

The Banquet speaker will be David S. Lewis, chairman and chief executive officer, General Dynamics Corporation.

Many members will return to the Grand Ballroom on Saturday n i g h t to dine and dance the evening away to the strains of the Steven Scott Orchestra, at SNAME's Annual Dinner-Dance.

Technical Sessions The technical papers will be presented at the time listed in the accompanying chart and in the rooms shown.

The technical papers are: Paper No. 1—"Development of Protective Covering Systems for Steel and Bronze Ship Propellers" by Francis J. Dashnaw, Ambrose A. Hochrein Jr., Robert S. Weinreich.

Paul K. Conn and Ivan C.

Snell.

SYNOPSIS — This paper reports on the development of elastomeric covering systems suitable for the protection of the surfaces of steel and bronze ship propellers. The development of covering systems f o r steel propellers will reduce the capital costs of propellers and the cost of cathodic protection by providing the necessary protection against cavitation erosion, erosion and galvanic corrosion while providing a smooth surface.

For existing bronze propellers, the covering systems will reduce cavitation erosion damage and cathodic p r o t e c t i o n requirements, and improve propulsion efficiency.

Paper No. 2 — " E f f e c t s of Hull F o u l a n t s and Cleaning/Coating Practices on Ship Performance and Economics" by John Austin Malone, David E. Little and Michael Allman.

SYNOPSIS — Relationships between the parameters of ship design, operation and economics affected by hull surface condition are discussed and integrated in a Hull Performance A s s e s s m e nt Model. Exercises of this model demonstrate that significant benefits are attainable through the optimization of hull recoating and in-situ cleaning schedules. The model is shown to be a practical tool to assess alternative hull surface management practices for widely varying ship types, operating profiles and economic scenarios.

Paper No. 3—"Liquid Dynamic Loads in LNG Cargo Tanks" by Robert L. Bass III, E.B. Bowles and P.A. Cox.

SYNOPSIS — This paper evaluates dynamic sloshing loads in LNG cargo tanks, and reviews worldwide scale model sloshing data for the purposes of defining design load coefficients. Analytical methods are presented which provide techniques for determining wall structural response to dynamic slosh loads. A methodology is given for designing various tank structures affected by dynamic slosh loads.

Paper No. 4—"Service Experience with 125,000-m3 LNG Vessels of Spherical Tank Design" by Joseph J. Cuneo, George A. Gilmore and Edmund G. Tornay.

SYNOPSIS—This paper describes the development and start-up of the Indonesia-Japan LNG trade, and provides the characteristics of the eight U.S.-flag 125,000-m3 LNG vessels used in the trade.

Also discussed are gas trials and voyage characteristics, improvements based on service experience, including modifications to cargo and ballast system components, the main reduction gear, and internal components of the boilers. Design of the cargo control system and reliability in electronic control systems are the most critical factors in determining the operation effectiveness of LNG vessels.

Paper No. 5—"Technology Survey of Major U.S. Shipyards" by Robert Lowry, William L. Stevens and John D.F. Craggs.

SYNOPSIS—This is a report on a technology survey of 13 major U.S. shipyards and 16 comparable foreign shipyards. Over 2,000 technology level determinations are placed in perspective with the results presented in terms of comparison among U.S. shipyards and between US. and foreign shipyards.

The results identify areas where U.S. shipyards could improve their efficiency.

Paper No. 6—" A Rational Methodology for the P r e d i c t i o n of Structural Response Due to Collisions of Ships" by Pin Yu Chang, Frederick Seibold and Chirasak Thasanatorn.

SYNOPSIS — A rational methodology based on a synthesis of the modern finite element techniques, the collapse theorems, and the experimental data from collision tests is proposed for the prediction of the collision impact force and structural damages. The difficulties of the existing approaches also are discussed.

Paper No. 7—"Practical Design Approaches for the Analysis of Barge Performance in Offshore Transportation and L a u n c h i ng Operations" by Rubin Szajnberg, William Greiner, Henry T. Chen and Philip Rawstron.

SYNOPSIS — The problems and solution techniques encountered in quantifying the safety factors involved in the transportation of large offshore structures on deck cargo barges form the basis of this paper. The primary factors considered are e n v i r o n m e n t al force prediction, stability, motion and strength, and their interaction which forms criteria for selecting an acceptable barge/jacket c o n f i g u r a t i o n for towing and launching operations. The methodologies are presented and compared in light of the state-of-theart in naval a r c h i t e c t u r e and structural analysis.

Paper No. 8—"Motions and Hydrodynamic Loads of a Ship Advancing in Oblique Waves" by C.H. Kim, Frank S. Chou and David Tien.

SYNOPSIS — Application of a strip method are made evaluating the following: wave- and motioninduced forces and moments, response motions, wave loads on cross-section and relative motions of vessels of diverse configurations ; also ocean bottom effects on ship motions and speed effects on roll damping. Less favorable results are shown for shorter waves and higher ship speed.

Paper No. 9—"Ship Maneuvering and Control in Wind" by Leonard L. Martin.

SYNOPSIS—This paper examines the effects of wind on the control and turning of ships in general (rather than specific ships as in previous studies), identifies the major parameters d e t e r m i n i ng the several possible modes of behavior, describes possible ways of measuring course-keeping behavior by ship trials, and ends with some recommendations for design for satisfactory handling in wind.

Paper No. 10 — "Measurement of Hydrodynamic Characteristics from Ship Maneuvering Trials by System Identification" by Martin A. Abkowitz.

SYNOPSIS — System identification techniques were developed for the purpose of determining the hydrodynamic coefficients in maneuvering of the ship f r om the measurement of the motion responses resulting from rudder action during ship trials. These techniques were used to specify the trial maneuvers of the Esso Osaka (VLCC), and to "measure" the ship's hydrodynamic characteristics from the data obtained during these trials.

Paper No. 11—"Guidelines for Prevention of Excessive Ship Vibration" by Helge Johannessen and Knut T. Skaar.

SYNOPSIS—The authors describe when and how to do what by the use of simple formulas. They suggest the minimum number of investigations necessary for making the designer qualified to take the first decisions in the evaluation process without assistance from vibration experts. Costly and time-consuming calculations are recommended only when serious vibration problems may occur.

Paper No. 12—"Hydroelasticity and Vibrations of Internal Steelwork of Tanks" by Guy C. Volcy, Michele M. Baudin, Michel D.

Bereau and Francois G. Besnier.

SYNOPSIS — Theoretical studies aimed at solving the problem of vibrations revealed the lack of a rational method for taking into account an important parameter, the apparent supplementary mass (called virtual added mass of fluid). It was necessary to estabblish a program including fluid finite elements and coupling ele- ments with solid elements used by F.E.M. calculations, enabling the designer to proceed with such calculations and correctly treat the concerned vibratory problems.

The paper presents the results of these theoretical studies concerning F.E.M. modelization of the steelwork and calculations of free vibrations in air and in fluid of the assembly of a transverse ring of a tanker, calling for lumped masses and fluid finite-element methods. The correlation with measurements also is presented.

Paper No. 13 — "Notes on Thrusters for Ship Maneuvering and Dynamic Positioning" by Ralph A. Norrby and Donald E.

Ridley.

SYNOPSIS—This paper presents the historical d e v e l o p m e n t of thrusters as maneuvering aids, as well as current thruster types and their applications. Various aspects of mechanical design are discussed including gears, bearings and seals. Hydrodynamic considerations based on model testing are explored, and a merit coefficient based on the work of Bendemann is proposed for use. In addition, thruster controls and sources of vibration and noise are addressed.

Paper No. 14—"Early Design- Stage Approach to Reducing Hull Surface Forces Due to Propeller Cavitation" by Kjell Olav Holden, Odd Fagerjord and Ragnar Frostad.

SYNOPSIS — The authors have based their paper on regression analysis of data from model wake field measurements and full-scale investigations. Recommendations on selection of afterbody lines to reduce the wake peak are given for both slender V-shaped and full-form ships. Presented are criteria for acceptable pressure fluctuations on the hull which should give satisfactory local vibration level in the afterbody structure as well as global vibration levels in the accommodation area. As a basis for further investigations, more specific guidelines are presented on selecting main propeller parameters and clearances, and a proposal on using the developed methods in a complete procedure is made.

Discussions of the papers, both written and oral, will be given after each paper to the extent that time permits.

Special Events Business Session—The Annual Business Session will immediately follow the presentation and discussion of Paper No. 5 in the Trianon Ballroom at 4:00 p.m.

on Thursday, November 13. The agenda for this meeting will include the election of the president of the Society, consideration of proposed amendments to the Bylaws, a report of the elections which occurred at the Council Meeting on Wednesday, and such other business as may be introduced by the Chair.

Ladies' Hospitality and Information —- A special area will be set aside in the East Promenade, third floor, from 9:00 a.m. to 4:00 p.m. Thursday and Friday for SNAME ladies and their guests to pick up information on places to visit and things to do and see in New York. Maps, brochures and other helpful suggestions will be available. Coffee will be served.

Authors' Breakfast — Authors, presiding officers and assistant presiding officers will meet at breakfasts on the days of thensessions at 7:30 a.m. on Thursday in Suite 524, and on Friday in Suite 520.

Sections Committee Breakfast —Breakfast will be served on Thursday in Suite 526 at 7:30 a.m.

Membership Committee Breakfast— Yearly meeting will be held at breakfast on Friday in Suite 517 at 7:30 a.m.

President's Luncheon — A general reception will be held in the West Ballroom Foyer at 12:00 noon on Thursday prior to the President's Luncheon. The President's Luncheon will begin at 12:30 p.m. in the West Ballroom on the third floor. Featured on the program will be the presentation of several important awards and an address by the president of the Society.

Annual Banquet — The 88th Annual Banquet will take place on Friday evening, November 14, starting at 7:30 p.m.

Dinner-Dance — The Dinner- Dance will be held in the Grand Ballroom on Saturday, November 15. A reception will be held in the Grand Ballroom Foyer starting at 7:00 p.m. The Dinner- Dance will start at 8:30 p.m.