Annual report 1972
Netherlands Ship Model Basin
Wageningen the Netherlands
Corïii:Hii;iii:: • P r o s p e c t s Facilities in Wageningen Events in 1972 10 11
Board of Directors, IVIanagement, Advisory Board, Con= 1 sultants. Representatives
•3 GerK=!i'ail
Industrial S e r v i c e
Deep water towing tank
Cavitation tunnels and special projects 5 Strength and vibrations
Depressurized towing tank Propulsion hydrodynamics Seakeeping basin
Wave and current basin Shallow water basin Manoeuvring simulator Computer centre General
Development of service programs Service to industry
R e s e a r c h
Instrumentation
Cooperation w i t h other organizations Personnel
Publications, lectures, meetings
16 18 18 18 18 20 21 22 23 24 32 Some important figures
34 35
Organization scheme and principal personnel of the NSMB 36 Amount of orders from the Netherlands, foreign countries and NSMB research 37
Board of Directors, Management, Advisory Board,
Consultants, Representatives
Board of Directors (Dutch)
Chairman Vice-Chairman Secretary IVIembers J . W. Hupkes Shipbuilder (retd.) Dr H. J. H. Janssen
Under-Secretary of State for Shipping P. de Josselin de Jong
Shipowner (retd.) Prof. H. E. Jaeger Naval Architect (retd.)
R. J . H. Fortuyn
Floyal Netherlands Shipowners Association P. E. E. Kleyn van Willigen
Shipowner
0 . J . van der Vorm
Central Association of Dutch Shipbuilders 0 . W . Vos
Ministry of Finance
IVIanagement
President Prof, dr J . D. van Manen
Vice-Presidents A. H. Pastoor, Registeraccountant (Administration)
Dr J . P. Hooft
(Ship Dynamics - Offshore Technology) J . J . Muntjewerf
(Ship Powering) Dr M. W. C. Oosterveld
(/Research and Development)
A d v i s o r y B o a r d
Members W. C. den Hartog Shipbuilder (Dutch) A. Laredo
Shipbuilder (French) J . F. Meijer
Royal Netherlands Navy G. Nilsson
Shipbuilder (Swedish) H. M. Oudshoorn
Ministry of Transport, Hydraulics and Public Works (Dutch)
E. M. O. Roren
Det norske Veritas (Norwegian) L. P. Ruys
Shipowner (Dutch) M. C. van Veen Shipbuilder (Dutch)
Prof. W. Vinke
University of Tecfinology, Delft (Dutch)
C o n s u l t a n t s (Dutch) Prof. J . Gerritsma
University of Technology, Delft Prof, dr W. P. A. van Lammeren
Netherlands Ship Model Basin, Wageningen (retd.)
Prof, dr R. Timman
University of Technology, Delft Prof, dr R. Wereldsma
University of Technology, Delft
R e p r e s e n t a t i v e s Antelope Engineering Pty., Ltd., Milson's
Point, N.S.W. Australia
J . E. Bowker & Associates Inc., Boston U.S.A. and Canada
Mr Blakely Smith, Houston U.S.A., Gulf area
MacGregor Far East Ltd., Tokyo Japan
Nafsi S.A., Piraeus Greece
General
On June 9, H. R. H. Prince Glaus of the Netherlands inaugurated the depres-surized towing tank in Ede.
On March 22, prof, dr W. P. A. van Lammeren retired from his office as president after a period of 42 years of active service. He was succeeded by prof, dr J. D. van Manen, who joined the staff of the NSMB in 1948.
The 40th anniversary of the NSMB was celebrated from August 29 - September 1. A great number of international experts assisted in the organization of the symposium by submitting outstanding technical papers. The papers in the mean-time have been compiled in a jubilee book.
In November Mr D. Rodenburg, secretary, and dr H. H. Mooij retired from their membership of the Board of Directors after 7, respectively 8 years of active service, Mr P. de Josselin de Jong accepted an appointment as secretary of the Board. Mr P. E. E. Kleyn van Willigen, Mr R. J. H. Fortuyn, the latter official represen-tative of the Royal Netherlands Shipowners Association, and Mr 0 . J . van der Vorm, official representative o f t h e Central Association of Dutch Shipbuilders were nominated as new members.
Her Majesty the Queen awarded the Chairman of the Board of Directors, Mr J . W. Hupkes, with the 'De Ruyter'-medal in gold in recognition and ap-praisal of his activities f o r t h e NSMB in the past 21 years. The medal was handed over on September 27 by the Secretary of State, Ministry of Transport, Hydraulics and Public Works, dr. R. J. H. Kruisinga, who stressed the importance of this mark of honour, which was created in 1907, 300 years after the birth of Admiral Michiel Adriaanszoon de Ruyter and is given to persons who have distinguished themselves by deserving achievements for Netherlands shipping. On May 9, the Advisory Board was installed by the chairman o f t h e Board of Directors, Mr J . W. Hupkes. The Advisory Board will assist the Board of Directors and the Management in appraising new ideas and developments of scientific industrial service in marine technology. For this reason the Advisory Board is composed of authorities from the shipbuilding, shipping and offshore industry, navy and university.
The Advisory Board met twice in 1972. The discussions promise a new technical communication between industry and the NSMB management.
A satisfying number of industrial orders was received during the year, main-taining the 'self-supporting' basis of the institute.
The large number of advanced projects under process at the end of 1972 pro-mises stable growth and continuity for the near future.
The table on page 33 gives some figures on the distribution of the turnover of the different facilities since 1968, as percentages of the total turnover. The graphs on pages 37 and 38 give an impression of where the orders originated from.
Industrial Service
Deep w a t e r t o w i n g tank
This facility was, as in previous years, fully occupied during the whole of 1972 with industrial orders. The work was carried out in t w o full shifts.
The tendency already evident in foregoing years for a gradually increasing de-mand for more complicated electronical measuring devices is continuing partly due to the nature of the tests to be performed, partly due to automation With regard to the latter, a first step has been made by recording the 5-hole Pitot tube wake surveys on magnetic tape.
The results are calculated and plotted immediately by a computer. The instru-mentation for the determination of the wave resistance by means of wave-cut analysis has been completed and the necessary software is ready for routine use. Besides the large number of normal resistance and propulsion tests some re-search work, sponsored by the Netherlands Ship Rere-search Centre TNO, has also been carried out.
Investigations with regard to the vibration and propulsive performance of a contra-rotating propeller arrangement as an alternative propulsion device for a third generation containership have been completed.
Open water tests with t w o geosim propeller models for an LNG tanker model have been conducted at a series of different Reynolds numbers to investigate the scale effect on propeller characteristics. Laminary flow effects have been observed for Reynolds numbers below 1.5 x I Q S . For this project also measurements have been started to study the wake and the boundary layer flow with hot-film anemo-meters. As could be expected, initial difficulties had to be overcome, which is normal with these advanced measuring devices. Boundary layer thickness measurements can now be conducted satisfactorily. Finally a start has been made to investigate fundamentally the effect of ventilation on the resistance of flat plates.
Cavitation tunnels and special projects
As in previous years, the cavitation tunnel with flow regulator has been used mainly for cavitation observation tests with propeller models.
In this tunnel the axial wake flow in the propeller plane can be simulated ac-curately by means of a flow regulator consisting of a multiple of channels with valves system. The amount of orders for this tunnel showed a slight increase with regard to the preceding year.
In the large cavitation tunnel most tests consisted of cavitation tests with pro-peller models and pressure fluctuation measurements on built-in ship after-bodies. The wake flow (axial, tangential and radial components) is simulated by the ship afterbody itself. In the beginning a standard forebody made of steel was
used for fixing the afterbody model. This way of simulating the wake flow proved to be unsatisfactory.
Later on, complete dummy models were built in, which showed a satisfactory simulation of the wake flow.
In the high speed cavitation tunnel a research program was carried out to es-tablish the effect of polymers on cavitation. Polymer solutions were injected from the nose of a cylindrical body made of stainless steei or Teflon. A definite reduction of both incipient and desinent cavitation was found for the stainless steel body, whereas a slight reduction was found for the Teflon body.
S t r e n g t h and vibrations
By means of the finite element computer program DASH, developed at the NSMB, the vibration level at service speed, as generated by the complete pro-peMer excitation system (hull pressure forces and dynamic propeller shaft forces and moments), has been calculated at several locations on a ship (thrustblock foundation, rudder stock, top deck of deckhouse). Good agreement with full scale measurements have been achieved.
For transverse shaft vibrations it has been found that the oilfilm in the bearings plays a very important role (stiffness and damping). The research on this subject T v i e n t T cooperation with the University of Technology,
Measurements of propeller induced pressure fluctuations on a dummy ship model m the large cavitation tunnel have shown to give good qualitative information with regard to the hydrodynamic hull excitation for most ships. For quantitative information the reproduction of the wake field is generally too difficult due to the restricted tunnel dimensions. Measurements in the depressurized towing tank, however, will result in accurate predictions of excitation forces on the full scale
As a result of the fact that the dynamic behaviour of cavitation has shown a large magnification effect on the hull pressure fluctuations, it was assumed that re-ducing the inhomogeneities of the wake field in the upper part of the propeller disc would lead to a considerable reduction of the pressure fluctuations For various ships a tunnel-like structure, just above the propeller and starting on the hull at some propeller diameters distance in front of the propeller has been successfully recommended resulting in substantial reductions of full scale hull vibrations.
Important progress has been made in developing an instrument for measuring the total propeller induced fluctuating force on the afterbody. Some orientating tests led to promising results.
Depressurized t o w i n g tank
The very first trials of this totally new facility proved that the conception, design and technology have been correct.
The pressure control of the tank and speed control of the carriage created no problems of significance.
The vacuum can be maintained at less than 33 mm Hg, using only a fraction of the available pumping power. This means that models up to a scale of 1 :30 can be tested under realistic cavitation conditions.
The speed of the carriage, which is computer controlled, can be kept within a tolerance of 1/000 of the required speed in the range of 0.8 to 4 m/sec. The force between the carriage and model can therefore be measured very accurate-ly, even with an 18 tons model.
Some problems conceming the reliability of the equipment under depressurized conditions were successfully solved.
The completely computerized measuring system is operational. The results can be reproduced within very narrow limits and indicate an interesting influence of cavitation on the interaction between ship and propeller.
The cavitation phenomena on the propeller can be clearly observed through both periscopes. Special light beams have been fitted to obtain an acceptable light distribution over the propeller.
There is a world wide interest in the results of tests under cavitating conditions. Reliable measurements were obtained towards the end of the year. It is therefore possible that a better analysis of propeller behaviour and its effects on the hull will be achieved.
A new equipment for the measurement of pressure fluctuations on the hull will become operational during 1973 together with equipment for measuring un-steady forces and moments on the shaft. The measuring equipment has a capa-city of up to 32,000 samples per second.
Cavitation on propeller blades of ship model in depressurized towing tank.j
Propulsion hydrodynamics
This recently formed department takes care of guiding and developing major theoretical work in the field of propulsion hydrodynamics. It is located in the offices of the depressurized towing tank in Ede.
In the past year analytical work has mainly been concentrated on the hydro-dynamical phenomena which influence the action of the propeller. This work has resulted in the further development of the linearized unsteady lifting surface theory and in the development of a quasi-steady theory for the calculation of cavitation on propellers. In addition, the cross-fairing of the Wageningen B-screw series was continued and a start was made in the preparation of a revised set of open-water and 'Bp-delta' diagrams.
The numerical unsteady lifting surface program can now, with success, be ap-plied to the determination of unsteady propeller loads and vibratory hydro-dynamical propeller characteristics. The quasi-steady cavitation analysis program IS primarily used for the analysis of propeller performance and propeller design. The results of a large number of experimental projects were analysed and inter-preted by means of these theories.
Attention is now being focussed on the influence of the Reynolds number on nominal wake, on propeller - wake induction effects and on propeller - hull mteraction phenomena inclusive of the influence of cavitation. In connection
W i t h the latter subject, work has recently been started on the development of a
theory for the calculation of the vibratory hull pressures and forces induced by cavitating propellers.
Finally, together with other departments, an experimental program has been started to assess the various devices available for measuring wake field velocities, The devices under consideration are the 5-hole and Prandtl Pitot-tube, the hot-film anemometer and the laser-doppler velocity meter.
Seakeeping basin
The large amount of industrial orders again made it necessary to carry out the experiments in this facility in double work-shifts.
More than 50 per cent of the work consisted of rendering service to the offshore-industry, characterized by a large diversity of the problems to be solved, parti-cularly in connection with the exploration and exploitation of minerals in unpro-tected waters of increasing depths.
Existing theories and computer programs proved indispensable to estimate in first instance the phenomena that can be expected. A remarkable tendency to substitute the traditional seakeeping experiments by model studies into local phenomena for maritime structures, platforms as well as surface ships became evident.
Apart from the investigations in the industrial sector, also some general research programs were completed, for example an investigation into the behaviour and the sustained sea speed in the scope of the development of a fourth generation container carrier.
W a v e and c u r r e n t basin
Compared with 1 9 7 1 , the wave and current basin was well provided with orders during the year under review.
Of the available time, 90 per cent was used for industrial orders. Studies to deter-mine the behaviour of moored or anchored vessels accounted for 50 per cent of the work. For 75 per cent of these studies emphasis was laid on the design of the mooring systems and the dimensioning of the mooring equipment. For the remaining 25 per cent of these studies, the dynamic motion behaviour and the forces in the construction constituted the most important aspects of the tests. These tests were carried out with such vessels as pipe-laying barges and dredgers.
Determination of the manoeuvring characteristics of ships, partly in order to be able to judge new ship designs, partly in order to obtain information to be used for the design of new waterways represented about 20 per cent of the orders. The reversed spiral technique was successfully introduced as a standard proce-dure to evaluate the dynamical course stability of ships.
Of the remaining orders the introductory investigation into the stability of the piers of the Hook of Holland harbour should be especially mentioned. This order was carried out for the Ministry of Transport, Hydraulics and Public Works under supervision of the Delft Hydraulics Laboratory.
As a result of the satisfactory number of orders in hand at the end of the year, the prospects for the coming year seem to be promising.
S h a l l o w w a t e r basin
The less favourable order situation during 1971 continued for the first half of the year. This period of slackness created a possibility for fundamental research by our institute. The following research programs were carried o u t :
- captive model tests to determine the hydrodynamic coefficients of a 200 000 TDW tanker in loaded and ballast condition in deep water, in behalf of the ma-noeuvring simulator;
- oscillator tests to determine the influence of the water depth on the hydro-dynamic coefficients of a tanker for motions in the horizontal plane •
- measurements of wave forces on t w o neighbouring cylinders and on a pyra-mid to check the results of the computer program for the calculation of the wave forces on bodies of arbitrary shape, the completion of which was reported in the preceding annual report;
- a start was made with systematic open water tests with controllable pitch propellers in nozzles.
During the second half year the tank was fully occupied again with commercial work. The turnover was composed as f o l l o w s :
percentage
manoeuvring tests 15 tests in waves and oscillator tests 50
resistance and launching tests 25 theoretical calculations i o The prospects for the next year are good.
Propulsion test with sternwheel riverboat model shallow water basin.
Manoeuvring simulator
The number and variety of activities on the manoeuvring simulator showed a sharp mcrease during the year. In the beginning of the year training courses in manoeuvring large tankers were conducted successfully for companies, which became regular clients for such courses. During the second half of the year various research projects were carried out besides the manoeuvring courses These projects included a program to establish the width and shape of an ap-proach channel to a proposed harbour, a program to evaluate different steering systems for large tankers and several programs for the evaluation of navigational aids. During one of the latter an attempt was made to measure the stresses ex-perienced by persons navigating with these aids under various conditions. To carry out all these programs the simulator had to be operated in t w o shifts. The development of software for the simulation of new types of ships, different, tankers on shallow and deep water, and a container ship, required considerable effort and time for which the staff had to be extended.
The analysis of the results of the research programs contributed to the under-standing of how similar programs could be optimized and in which way further analysis can be refined.
The projection system of the simulator was improved to enable simulation of manoeuvres close to coasts and in harbour entrances. A radar simulator from Redifon, having all advantages of ship borne radar (true motion, anti-collision etc.) will be installed in the beginning of 1973.
It is believed that the experience and knowledge gained during this year con-stituted a solid base for work to be carried out in the future.
Manoeuvring simulator-Measurement of physical reactions of ship officer navigating under difficult conditions.
ANALYSIS
COWIPUTER
REGISTRATION
Manoeuvring simulator - In-vestigation into observational behaviour of officer on the bridge of a VLCC
C o m p u t e r c e n t r e
General
Since tfie CDC 3300 configuration has reached its full capacity during 1972 it was decided to purchase a PDP 11/45 computer system, equipped w i t h , among other thmgs, a visual display. This system will be especially devoted to the pro-cessmg of laboratory recordings and will be used as a batch terminal on a CDC 6600 computer.
The drawing capabilities of the computer centre were considerably increased by the mstallation of the KV 1890 drawing system, officially put into production on September 27. The drawing table has a net drawing area of 9.00 x i . 8 0 m. The new system has shown increased speed, reliability and drawing possibilities. Important was the streamlining of the software management. The different soft-ware groups were brought under one management. This will facilitate the diffi-cult task of integrating the software activities, which, by nature, are spread over many departments of the NSMB.
Development of service programs Design programs
New ideas and principles for a software package of design programs useful for different demands from clients were studied this year and some parametric stu-dies were carried out with the already existing tanker design program.
Shipyard production programs
Much effort was put into streamlining and further development of the NALS-programs used for the computer assisted preparation of papertapes for numeri-cally controlled flamecutting and drawing machines.
New programs for section supports and for templates for the bending process of shell plates have been developed. Specifications for these programs were ob-tained from an inquiry among the Dutch shipyards.
were intensively used during this year.
The decision, early in 1972, of Centraalstaal (Conoship group) to use the NALS-system (Numerical control Adapted Language for Shipbuilding) for the N/C equipment installed in their centralized steel preparation-shop has been followed by quite a few Dutch shipyards that make use of the large papertape controlled KV 1890 drawing machine of our institute.
The quality of the templates for shell plates produced by the drawing machine was so promising that several ship-yards decided to use the NALS geometry-describing language also for the internal plates of the ship structure.
As an obvious extension of our services to the industry the possibilities of terminal connections to the NSMB-computer are being studied. A market-analysis has been initiated for that purpose.
Coding courses were given for the part programmers of the shipyards as well as introductory courses for their staffs.
Computer centre - KV 1890 numerical controlled drawing table with net drawing area of 9 X 1,8 m.
Research
Research was continued on the recently found effects of cavitation on the vibra-tory forces acting at the stern of the ship. Therefore, as already mentioned under different headings in the previous chapter, much effort has been devoted in the past year for the development of :
- means for the determination of the wake field and the analysis of wake fields • - a propeller design method which includes the peripheral inequality of the wake in the design process;
- unsteady lifting surface theory for the determination of the propeller induced shaft forces. This theory will be extended to determine also the unsteady hull forces and to include the effect of cavitation in this theory;
- finite element methods including the effect of shear stresses and hydrody-namic mass, damping and coupling in hull vibration analysis.
The means and methods mentioned above were components in the research projects carried out for the Cooperative Research Program, the Netherlands Ship Research Centre TNO and the Royal Netherlands Navy.
At this moment 2 Dutch companies and 13 foreign companies, including 3 clas-sification societies, participate together with our institute in the Cooperative Research and Development of Large Tankers. The investigations concentrate on performance and cavitation, sealoads, propeller generated hull and shaft vibra-tions and manoeuvring of large tankers.
Much attention has also been given in the past year to the hydrodynamic aspects of semi-submersible platforms and underwater storage tanks. The theoretical methods for the calculation of the wave-excited forces on these constructions have been improved. A finite element method has been developed in combina-tion with the sealoads program which enables strength calculacombina-tions for semi-submersible platforms, underwater storage tanks and other constructions used for the exploration and exploitation of the seabottom.
Extensive model tests have been carried out during the past year to determine the hydrodynamic characteristics of large tankers sailing in shallow waters. These data are of utmost importance for studies to be performed at the manoeuvring simulator.
Instrumentation
The instrumentation for the depressurized towing tank was designed and in-stalled by this department.
Quite some time was used to adjust the several systems.
An active filter was installed to reduce the relative accelerations between model and carriage. This filter also serves as a protection of the resistance pick-up in the model against the very large starting and stopping forces.
Much time was also spent throughout the year to improve the quality, the quantity and the variety of the measuring equipment of the facilities in Wage-ningen.
In 1 972 a study was carried out to find a solution for the improvement of the recording of the data and the data reduction. The study, carried out with other departments, resulted in a new concept with the following advantages: great accuracy, more channels and the possibility of a faster data reduction.
The new set-up makes use of small PDP 11 / 1 0 computer configurations on the carriages and a large PDP 11 /45 system for the data reduction. The first con-figuration will be installed at the beginning of 1974.
Considerable time was spent on the design of a radar installation for the ma-noeuvring simulator.
Cooperation with other organizations
A regular communication with national and foreign institutions and organiza-tions in the field of marine technology was maintained.
A great number of authorities visited the new facilities of NSMB and dis-cussed problems of mutual interest.
Four members of NSMB have been selected in committees o f t h e International Towing Tank Conference:
Prof. dr. J. D. van Manen Advisory council Dr. M. W. C. Oosterveld Propeller committee J . J . Muntjewerf Performance committee M. F. van Sluijs Seakeeping committee P. van Oossanen Cavitation committee
f ^';'''°P^^".Conference on Marine Technology is planned in The Hague tor May 1974. This conference is a joint activity of the Royal Institution of Naval Architects, Institute of Marine Engineers, Association Technique Maritime et Aeronautique, Schiffbautechnische Gesellschaft and Koninklijk Instituut van Ingenieurs (Section Marine Technology). Prof. dr. J. D. van Manen has been elected as chairman of the executive committee.
Dr. J . P. Hooft became a member of Panel H-10 (ship controllability) of the Society of Naval Architects and Marine Engineers.
The cooperation with the Delft Hydraulics Laboratory, consisting of exchange of management information has developed fruitfully.
Continuous contacts were maintained with the Dutch Universities of Techno-^^I'Z Netherlands Navy, The Netherlands Ship Research Centre TNO and The Maritime Research Centre.
No. Title Author Published in 393a Wetenschappelijke
dienst-verlening aan scheeps-bouw en scheepvaart
J. D. van Manen
393a Toegepast wetenschappe-lijk onderzoek ten dienste van scheepsbouw en scheepvaart
3 9 7 * The effect of cavitation on the interaction between propeller and ship's hull 3 9 8 * Cavitation on
hemispheri-cal nosed teflon bodies 399 Incipient and desinent
cavitation on hemispheri-cal nosed bodies
400 Hydrodynamic aspects of semi-submersible plat-forms
4 0 5 * The effect of cargo hand-ling on ship operation economics
4 0 6 * Influence of N/C produc-tion on shipyard organiza-tion
4 0 7 * Note on mutual influence between transverse stabil-ity and roll motion 4 0 8 * Motion minimization of
semi-submersible barges 409 Ship research activities in
the Netherlands
410 Netherlands Ship Model Basin
411 * Thruster systems for im-proving the maneuverabil-ity and positionkeeping capability of floating ob-jects J . D. van Manen J . D. van Manen J . H. J. van der Meulen J . H. J . van der Meulen J. P. Hooft A. Koops A. W. Ruys
Tan Seng Gie
M. F. van Sluijs
M. W. C. Oosterveld and P. van Oossanen
M. W. C. Oosterveld and G.van Oortmerssen Schip en Werf, 1972, p. 368 Catalogus voor de Scheepvaart, 4de editie 1972-1973, p. 106 Polytechnisch Tijd-schrift, editie Werk-tuigbouw, 1972, p. 802 and 834 Nautisch Technisch Tijdschrift De Zee, 1972, p. 158 and 190 ISP, 1972, p. 3 ISP, 1972, p. 333 ISP, 1972, p. 21 NSMB, Wageningen, 1972 (Doctor's thesis) Europort '71 Congress Amsterdam, 'Nether-lands Day' (1972) Europort '71 Congress Amsterdam, 'Nether-lands Day' (1972) Europort '71 Congress Amsterdam, 'Nether-lands Day' (1972) Europort '71 Congress Amsterdam, 'Nether-'lands Day (1972) ISP, 1972, p. 213 NSMB, Wageningen, 1972
Fourth Annual Off-shore Technology Conference, Houston, Texas, 1972, Vol. II,
p. 87
No. Title Author
Published in 4 1 2 * Motion optimization of H. L. Minkenberg
semi-submersibles and M. F. van Sluijs
413 Het berekenen en tekenen H. Konijnenberg van huidplaatuitslagen met
het computerprogramma 'SHELL', ontwikkeld door het Rekencentrum van het Nederlands Scheepsbouwkundig Proefstation
4 1 4 * The ship as an integrated J . D. van Manen system
4 1 5 * Application of network A. W. Ruys analysis to the allocation
of capacity and to project cost control 4 1 8 * Cavitation testing of marine propellers 4 2 0 * Het Nederlandsch Scheepsbouwkundig Proefstation te Wageningen 421 On the use of a
ma-noeuvring simulator 4 2 2 * Hydrodynamics of the
re-P. van Oossanen J . J . Muntjewerf
I. Oldenkamp and J. P. Hooft
M. W. C. Oosterveld
Fourth Annual Off-shore Technology Conference, Houston, Texas, 1972, vol. II, p. 131 Schip en Werf, 1972, p. 349 Symp. 'Development in Merchant Shipbuilding', Design -Production - Manage-ment, Delft, 1972, Paper No. 1 Symp. 'Development in Merchant Shipbuilding', Design -Production - Manage-ment, Delft, 1972, Paper No. 14 Schip en Werf, 1972, p. 286 and 309 De Ingenieur, 1972, p. A574
Schiff und Hafen, 1972, p. 561
Devel-Date Subject Author Audience August 30 -September 1 October 28 Recent develop-ments in marine propeller hydrody-namics
Cavitation and its detrimental effects Retrospection on 15 years NSMB seakeeping activi-ties M. W. C. Oosterveld and P. van Oossanen J. H. J . van der Meulen M. F. van Sluijs and
Tan Seng Gie
Ocean technology J . P. Hooft Design and
opera-tions
Manoeuvring large ships in shallow water
November 1 5 Recent develop-ments of scientific industrial services at the NSMB November 21 The choice of
pro-peller design para-meters with respect to cavitation con-trol J . Holtrop and A. Koops J. P. Hooft J . D. Manen P. van Oossanen
U.S. Coast Guard Academy at New London,
Connecticut U.S. Coast Guard Academy at New London, Connecticut Hydromechanics Colloquium at Bethesda, Mary-land, organized by Naval Ship Re-search and Devel-opment Center
T h e f o l l o w i n g meetings w e r e attended in 1972 larch 13 larch 15 April 1 1 - 1 3 April 1 2 - 1 4 May 1-3 May 1 6 - 1 8 May 26 May 3 0 - J u n e 2 August 2 0 - 2 5
ITTC Propeller Committee at Feltham Symposium 'Modern ship structural design philosophy' at Delft, orga-nized by 'Sectie voor Scheepstech-niek van het Koninklijk Instituut van Ingenieurs'
ITTC Performance Committee in London
Spring Meetings of the Royal Institu-tion of Naval Architects in London and Haslar
Fourth Annual Offshore Technology Conference at Houston, Texas, spon-sored by the American Institute of Mining, Metallurgical, and Petrole-um Engineers et al.
SPE - European Spring Meeting in Amsterdam, organized by the Nether-lands Section of the Society of Pe-troleum Engineers (SPE) o f t h e American Institute of Mining, Metal-lurgical, and Petroleum Engineers (AIME)
North Sea Towing Tank Conference at St. Albans
Symposium 'Development in Merchant Shipbuilding', Design Production -Management at Delft, organized by the Sub-department of Naval Archi-tecture of the Delft University of Technology
Ninth Symposium on Naval
Hydro-J . D. van Manen J . D. van Manen, A. W. Ruys and Tan Seng Gie
J . J . Muntjewerf J. J . Muntjewerf, J . van der Kooy, P. van Oossanen and M. F. van Sluijs G. van Oortmerssen and M. F. van Sluijs
M. F. van Sluijs
J . D. van Manen J . D. van Manen and A . W . Ruys
August 2 9 - International Jubilee Meeting on the September 1 Occasion of the 40th Anniversary of the Netherlands Ship Model Basin in The Hague and Delft
September 4 - 1 4 September 22
September 2 6 - 2 8
November 1
13th International Towing Tank Con-ference in Berlin and Hamburg
Symposium 'Ontwerpen met de computer' at Eindhoven, underthe auspices of 'Afdeling voor Technisch Wetenschappelijk Onderzoek van het Koninklijk Instituut van Ingenieurs en het Nederlands Rekenmachine
Genootschap'
Third Ship Control Systems Sympo-sium at Bath, organized by the Ship
Department of the United Kingdom Ministry of Defence
Symposium on Jet Pumps and Ejec-tors in London, sponsored and or-ganized by BHRA Fluid Engineering
(The British Hydromechanics Re-search Association) in conjunction with the Institution of Chemical Engineers
November 1 6 - 1 7 Eightienth Annual Meeting of the So-ciety of Naval Architects and Marine Engineers in New York
Europort '72 Congress, 'Offshore Day' in Amsterdam, under the aus-pices of the Division for Underwater Technology of the Royal Institution of Engineers in the Netherlands ITTC Performance Committee in
Paris November 17 J . D. van Manen, J . P. Hooft, J . J . Muntjewerf, M. W. C. Oosterveld, J . Holtrop, A. Koops
J . H.J.van der Meulen, P. van Oossanen, M. F. van Sluijs and Tan Seng Gie
J. D. van Manen and J . J. Muntjewerf G. D. Draaijer and J . Holtrop J . P. Hooft W. van Gent December 7-8 J . D. van Manen M. W. C. Oosterveld and P. van Oossanen G. van Oortmerssen, G. F. M. Remery and M. F. van Sluijs
J . J . Muntjewerf
Prospects
The prospects for 1973 can be considered promising.
The increase of work since the middle of 1972 and the good distribution of orders over the various departments has continued in the first quarter of 1973. A limited extension of the staff will be necessary in view of the amount of work In hand and the further prospects for 1973.
Much attention, however, will also be given to a further mechanization or auto-mation of activities.
Some important figures
Turnover of different facilities in per cent of total turnover:
1968 1969 1970 1971 1972
Deep water towing tank
Propulsion hydrodynamics - cavitation
34 13 30 6 27 9 32 10 30 8
Total, Ship Propulsion 47 36 36 42 38
Wave and current basin Seakeeping basin Shallow water basin Manoeuvring simulator 22 16 9 32 20 6 29 •| 1 12 1 13 25 8 5 21 19 7 11 Total, Ship hydrodynamics - Offshore
technology 47 58 59 51 58
Computer centre 6 6 5 7 4
Total turnover NSMB, per cent 100 100 100 100 100
Orders from foreign countries in per cent of total turnover
58 50 53 64 58
NSMB research in percent of total turnover 12 16 10 24 19
Total income (turnover and other income) in per cent related to 1968
(Dfl. 9,191,000,-) = 100
Index of cost of living related to 1968 = 100 100 100 110 107.5 122 112.2 115 120.7 131 130.2 Personnel 311 311 339 337 3 2 3 *
* Of which 40 are in Ede
Events in 1972 March 22 April 28 May 9 May 24 June 9 June 14 August 18 August 2 9 -September 1 September 27 November 29
Prof, dr W. P. A. van Lammeren retired as President of the NSMB.
Prof, dr J . D. van Manen appointed President of the NSMB. Prof, dr J . D. van Manen awarded with the Gold Medal of the Royal Institution of Engineers in the Netherlands, Section Mechanical Engineering and Naval Architecture.
40th Anniversary of the NSMB.
Installation of the Advisory Board of the NSMB.
Assignment of the depressurized towing tank by designers and building team to the NSMB.
Official start of the experimental phase of the depressurized towing tank by H. R. H. Prince Glaus of the Netherlands. The NATO Information Exchange Group 6 'on ship design' of the NATO Naval Armaments Group visited the NSMB.
First propulsion test under vacuum carried out successfully. International jubilee meeting on the occasion of the 40th anniversary of the NSMB.
Mr J . W. Hupkes, chairman of the Board of Directors of the NSMB, awarded with the 'De Ruyter'-medal in gold.
The numerically controlled drawing machine (scale 1 :1) was put in operation by His Excellency dr R. J . H. Kruisinga, Secretary of State of the Ministry of Transport, Hydraulics and Public Works.
The Ambassador of the United States of America, Mr J . W. Middendorf II, visited the NSMB.
O r g a n i z a t i o n s c h e m e and principal personnel of the IMSMB
M a n a g e m e n t P r e s i d e n t
Prof. dr. J . D. van Manen
V i c e - p r e s i d e n t s
A. H. Pastoor, Reg. Acc. Dr. J . P. Hooft J . J . IVluntjewerf
Dr M. W. C. Oosterveld
A d m i n i s t r a t i o n
A. H. Pastoor, Reg. Acc.
S h i p p o w e r i n g J . J . IVluntjewerf R e s e a r c h and d e v e l o p m e n t Dr M. W. C. Oosterveld S h i p D y n a m i c s - O f f s h o r e t e c h n o l o g y Dr J . P. Hooft
Finance and personnel J. F. Meijer General secretariate F. W. J . van Bochoven J . Kools Maintenance section Domestic section
Planning and information
W. Verschuur J . Esveldt
Instrumentation
E. R. Dolfin C. M. J . Gommers
Deep water towing tank
A. Jonk
M. P. van der Veen
Industrial service connected with powering and cavitation in
Depressurized t o w i n g tank Cavitation tunnels Shallow water basin High speed t o w i n g tank
Ship trials
H. J . de Jonc
Drawing office and data processing of steady phenomena
J. Kamps W. H. a u f m Keller
Depressurized towing tank
G. Kuiper W. van den Berg S. van den Brand
Computer centre Hardware control W. Verschuur A. de Jong Software control A. Koops J . Holtrop G. D. Draaijer A. C. J . W. Oomen Industrial service A. W. Ruys P. Kiers
Wave and current basin
G. F. M. Remery J . A. Pinkster
E. G. Kruithof
Seakeeping basin and high speed towing tank M. F. van Sluijs S. G. Tan H. L. Minkenberg H. Rijken C. Flokstra
Shallo w water basin
G. van Oortmerssen L. J . Boreel
Million Dutcii Guilders
• 1971
131972
Tiie Netherlands Foreign countries NSiVlB Research
Amount of orders from the Netherlands, foreign countries and NSMB research in million guilders
