annual reporl
netheriands
B o a r d o f D i r e c t o r s , M a n a g e m e n t , A d v i s o r y B o a r d , C o n s u l t a n t s , R e p r e s e n t a t i v e s a b r o a d 1 G e n e r a l 3 I n d u s t r i a l s e r v i c e 4 Deep w a t e r t o w i n g tank 4 C a v i t a t i o n t u n n e l s a n d special projects 5 S t r e n g t h and v i b r a t i o n s 6 Depressurized t o w i n g t a n k 1 0 P r o p u l s i o n h y d r o d y n a m i c s 1 2 S e a k e e p i n g basin 1 4 H i g h speed basin 1 6 W a v e a n d c u r r e n t basin 18 S h a l l o w w a t e r basin 2 0 M a n o e u v r i n g s i m u l a t o r 2 2 C o m p u t e r centre 2 4 General 2 4 Software development 2 4
Shipyard production programs 2 6
I n s t r u m e n t a t i o n 2 7 P e r s o n n e l 2 8 P r o s p e c t s 2 9 S o m e i m p o r t a n t figures 3 0 D i s t r i b u t i o n of t u r n o v e r a n d N S M B research 31 P u b l i c a t i o n s , lectures, m e e t i n g s 3 2 Facilities in W a g e n i n g e n 4 0 O r g a n i z a t i o n s c h e m e and p r i n c i p a l personnel o f t h e N S M B 41
Board of Directors, Management, Advisory Board, Consultants,
Representatives Abroad
B o a r d o f D i r e c t o r s
C h a i r m a n J . W . Hupkes Shipbuilder (retd.)
V i c e - C h a i r m a n Dr, H. J . H. Janssen Under-Secretary of State for Shipping Secretary P. de Josselin de J o n g Shipowner (retd.)
M e m b e r s R, J . H. F o r t u y n Royal Netherlands Shipowners Association P, E. E. Kleyn v a n W i l l i g e n Shipowner
Prof. dr. W . P. A . van Lammeren Former President NSMB 0 . J . van der V o r m Central Association of Dutch Shipbuilders 0 . W . Vos Ministry of Finance
M a n a g e m e n t
President Prof. dr. J . D. v a n M a n e n
V i c e - P r e s i d e n t s A. H. Pastoor, R e g i s t e r a c c o u n t a n t Administration and Finance Dr. J . P. H o o f t Ship Dynamics - Offshore Technology J . J . M u n t j e w e r f Ship Powering
Dr. M . W . C. Oosterveld Research and Development
A d v i s o r y B o a r d
M e m b e r s W . C. d e n H a r t o g Shipbuilder A . L a r e d o Shipbuilder (France) J . F. Meijer Royal Netherlands Navy G. Nilsson Shipbuilder (Sweden)
H. M . O u d s h o o r n Ministry of Transport, Hydraulics and Public Works E. M . Q. Roren Det norske Veritas (Norway)
L. P. Ruys Shipowner J . W . M a i n g a y Shipbuilder
C o n s u l t a n t s Prof. J . Gerritsma University of Technology, Delft
The n u m b e r of industrial orders received d u r i n g t h e year w a s again s a t i s f y i n g . These orders w e r e w e l l spread over t h e various facilities and laboratories. T h e ' s e l f - s u p p o r t i n g ' basis of t h e institute c o u l d again be m a i n t a i n e d t h i s year. T h e a d v a n c e d projects under process at t h e end of 1 9 7 3 are in m a n y cases of a m u l t i - d i s c i p l i n a r y character. The n u m b e r of these projects make a further g r o w t h necessary a n d promise c o n t i n u i t y for the near f u t u r e .
T h e t a b l e o n page 3 0 gives s o m e figures o n t h e d i s t r i b u t i o n of t h e t u r n o v e r of t h e different facilities since 1 9 6 8 , as percentages of t h e total t u r n o v e r . T h e g r a p h on page 31 gives an impression of w h e r e t h e orders o r i g i n a t e d f r o m . In M a y prof. H. E. Jaeger retired f r o m m e m b e r s h i p o f t h e Board of Directors after t e n years of active service.
On O c t o b e r 1 6 , t h e Secretary of State for Transport and Public W o r k s , dr. M . fH. M . v a n H u l t e n a t t e n d e d d e m o n s t r a t i o n s at t h e S h i p M a n o e u v r i n g S i m u -lator a n d the Depressurized T o w i n g Tank.
In N o v e m b e r prof. dr. W . P. A . v a n Lammeren retired as a c o n s u l t a n t of t h e N S M B and w a s a p p o i n t e d a m e m b e r of t h e Board of Directors.
In December prof. W . V i n k e , a m e m b e r of t h e A d v i s o r y B o a r d , past a w a y . In t h e course of t h e year Mr. M . C. v a n Veen w a s replaced o n his request as a m e m b e r of t h e A d v i s o r y C o u n c i l by Mr. J . W . M a i n g a y .
On N o v e m b e r 1 an ' o p e n d a y ' o n t h e o c c a s i o n of t h e ' 2 5 years active service' j u b i l e e of prof. dr. J . D. v a n M a n e n w a s o r g a n i z e d .
O n N o v e m b e r 2 8 - 2 9 - 3 0 , t h e a n n u a l N S M B - s y m p o s i u m w a s a t t e n d e d by 4 0 0 visitors. T h e t h e m e of t h i s s y m p o s i u m w a s ' S h i p H a n d l i n g ' . T h e a u d i e n c e consisted of representatives of 2 2 countries, viz. representatives of M i n i s t r i e s
Industrial Service
D e e p w a t e r t o w i n g t a n k
This f a c i l i t y w a s , as in previous years, f u l l y o c c u p i e d d u r i n g t h e w h o l e of 1 9 7 3 w i t h industrial orders. T h e w o r k w a s carried o u t in t w o f u l l shifts.
T h e a u t o m a t i o n of 5 - h o l e Pitot t u b e w a k e surveys, by w h i c h t h e results are r e c o r d e d o n m a g n e t i c tape a n d next c a l c u l a t e d a n d p l o t t e d by a c o m p u t e r , has been c o m p l e t e d .
Besides t h e large n u m b e r of n o r m a l resistance a n d p r o p u l s i o n tests, s o m e research w o r k , s p o n s o r e d by t h e Netherlands S h i p Research Centre T N O , has been carried o u t .
W i t h t w o g e o s i m s h i p m o d e l s of an L N G tanker (similar in shape b u t d i f f e r e n t in scale r a t i o ) , b o u n d a r y layer measurements w e r e m a d e w i t h a n d w i t h o u t r u n n i n g propeller.
W a k e m e a s u r e m e n t s w e r e c a n i e d o u t w i t h 5 - h o l e Pitot t u b e s a n d Prandtl t u b e s ( 2 - h o l e Pitot t u b e s ) f o r c o m p a r i s o n .
A first a t t e m p t has been m a d e t o investigate t h e f e a s i b i l i t y of 3 - d i m e n s i o n a l w a k e m e a s u r e m e n t s w i t h laser e q u i p m e n t .
In close c o - o p e r a t i o n w i t h a s h i p o w n e r preparations w e r e c o m p l e t e d t o c o n d u c t c a v i t a t i o n o b s e r v a t i o n s of struts a n d propellers of a large t w i n s c r e w c o n t a i n e r s h i p at sea.
C a v i t a t i o n t u n n e l s a n d s p e c i a l p r o j e c t s
A n increased n u m b e r of c a v i t a t i o n o b s e r v a t i o n tests w i t i i propeller m o d e l s w e r e made in t h e c a v i t a t i o n t u n n e l w i t h f l o w regulator.
T h e large c a v i t a t i o n t u n n e l w a s intensively used f o r c a v i t a t i o n tests and m e a -s u r e m e n t of pre-s-sure f l u c t u a t i o n -s o n b u i l t - i n -s h i p m o d e l -s . T h e w a k e field-s o b t a i n e d w i t h t h e s e b u i l t - i n s h i p m o d e l s are q u i t e satisfactory for t w i n - s c r e w ships b u t for s i n g l e - s c r e w ships t h e y are d e p e n d e n t o n t h e s h i p ' s size a n d other particulars. In t h o s e cases c o m p l e t e ship models have t o be built and tested in t h e depressurized t o w i n g t a n k .
Furthermore, in t h e large c a v i t a t i o n t u n n e l tests w e r e made o n t h e p e r f o r m a n c e of d u c t e d propeller systems and o n t h e blade s p i n d l e t o r q u e of c o n t r o l l a b l e p i t c h propellers.
T h e circular test section of t h e h i g h speed c a v i t a t i o n t u n n e l has been replaced by a rectangular o n e . This enables a s t u d y of scale effects on profiles.
In c o - o p e r a t i o n w i t h t h e O p t i c s D e p a r t m e n t o f t h e Institute of A p p l i e d Physics T N O - T H an i n v e s t i g a t i o n w a s m a d e o n t h e use of l a s e r - h o l o g r a p h y for m e a s u r i n g t h e b u b b l e s p e c t r u m in w a t e r . T h e m e t h o d w i l l be used f o r a s t u d y of c a v i t a t i o n i n c e p t i o n o n a standard h e a d f o r m .
S t r e n g t h a n d v i b r a t i o n s
Several series of m e a s u r e m e n t s of thie h u l l pressures w i t h c a v i t a t i n g a n d n o n -c a v i t a t i n g p r o p e l l e r s have been s u -c -c e s s f u l l y p e r f o r m e d in t h e depressurized t o w i n g t a n k . S o m e d i s t u r b a n c e s d u e t o v i b r a t i o n s of t h e s h i p m o d e l h u l l have been r e d u c e d t o an a c c e p t a b l e level by means of a special s u p p o r t of t h e s h a f t i n g w i t h t h e propeller a n d by r e d u c i n g t h e hull response.
T h e e l e c t r o d y n a m i c c o u n t e r b a l a n c e d f o r c e m e a s u r i n g d e v i c e has been c o m p l e t e d . This d e v i c e , w h i c h has been d e v e l o p e d for m e a s u r i n g t h e t o t a l p r o p e l l e r i n d u c e d h y d r o d y n a m i c hull f o r c e , s h o w s a m u c h smaller s e n s i t i v i t y f o r d i s t u r -bances t h a n n o r m a l pressure p i c k - u p s d o .
From c o m p a r i s o n s b e t w e e n t h e test results w i t h this m e a s u r i n g d e v i c e a n d t h e results w i t h t h e pressure p i c k - u p s it appeared necessary t o refine t h e c a l c u l a t i o n t e c h n i q u e f o r t h e i n t e g r a t i o n of t h e pressure m e a s u r e m e n t s o n t h e a f t e r b o d y t o o b t a i n t h e t o t a l h u l l skin forces.
A f t e r t h e first s u c c e s s f u l a p p l i c a t i o n of t h e f i n i t e e l e m e n t c o m p u t e r p r o g r a m D A S H in hull v i b r a t i o n analysis, a s e c o n d s h i p is n o w b e i n g analysed f o r propeller g e n e r a t e d h u l l v i b r a t i o n .
T h i s p r o g r a m is f r e q u e n t l y used f o r t h e i n v e s t i g a t i o n of propeller s h a f t resonances a n d f o r c e d v i b r a t i o n s .
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excitation frequency
Vibrations calculated w i t h a 3-dimensional finite element representation of an entire ship in response to propeller generated excitation forces measured in the model tank. As an example the calculated longitudinal thrust collar vibrations are s h o w n .
For comparison the results of full scale measurements on the actual ship are given as performed by Germanischer Lloyd.
P o r t
Stbd
The propeller-induced hydrodynamic hull excitation forces are determined by inte-grating the pressure fluctuations at some 20 points on the afterbody. In the Figure on this page an example is given of the location of 1 9 pick-ups. The signals from these pick-ups, induced by a 5-bladed propeller and measured in the depressurized t o w i n g tank are s h o w n in the Figures on the next page. It has to be noticed that the pressure amplitudes per cm vertical scale of the registrations measured under the depressurized condition (cavitation I) are 3.33 times larger than those measured under the atmospheric condition.
D e p r e s s u r i z e d t o w i n g t a n k
T h e e f f i c i e n c y of o p e r a t i o n of t h i s f a c i l i t y increased r a p i d l y after s o m e initial p r o b l e m s w i t h t h e e q u i p m e n t under depressurized c o n d i t i o n s w e r e s o l v e d . T w o shifts w e r e necessary t o h a n d l e t h e industrial orders s i m u l t a n e o u s l y w i t h research t o be d o n e t o o b t a i n i n s i g h t in t h e t a n k p h e n o m e n a a n d c o r r e l a t i o n w i t h t h e f u l l scale.
Full a d v a n t a g e c o u l d be t a k e n of t h e tests w i t h propellers o p e r a t i n g in c a v i t a t i n g c o n d i t i o n s in t h e w a k e b e h i n d t h e s h i p m o d e l . This a d v a n t a g e also p r o v e d t o be very i m p o r t a n t d u r i n g hull pressure m e a s u r e m e n t s , w h i c h w e r e p e r f o r m e d s u c c e s s f u l l y . T h e large m o d e l size increased t h e a c c u r a c y of w a k e m e a s u r e m e n t s T h e c o m p u t e r i z e d m e a s u r i n g system w o r k e d very satisfactorily. T h e m a i n e f f o r t in 1 9 7 4 w i l l be d e v o t e d t o a fast c o m p u t e r i z e d e v a l u a t i o n of t h e m e a s u r e m e n t s . Tests in t h e depressurized t o w i n g t a n k are m u c h in d e m a n d . M a n y p r o b l e m s can be a t t a c k e d w i t h t h i s u n i q u e f a c i l i t y a n d it w i l l require every e f f o r t t o f u l f i l t h e d e m a n d s of c l i e n t s a n d t o keep delivery t i m e s at a reasonable level.
P r o p u l s i o n h y d r o d y n a m i c s
T h e usefulness of m o d e l e x p e r i m e n t s o n resistance a n d p r o p u l s i o n of ships d e p e n d s s t r o n g l y o n t h e q u a l i t y of t h e c o r r e l a t i o n b e t w e e n m o d e l scale data a n d f u l l scale p r a c t i c e . A s t h e k n o w l e d g e of this correlation o b t a i n e d by e x p e r i m e n t s o n f u l l scale is restricted t o isolated cases, t h e o r e t i c a l means are r e q u i r e d , w h i c h have t o cover a w h o l e range of d i f f e r e n t parameters. M o r e e f f i c i e n t i n d u s t r i a l service by i m p r o v e m e n t of e x p e r i m e n t a l facilities, t o o b e y more a n d m o r e t h e g o v e r n i n g s c a l i n g l a w s (depressurized t o w i n g t a n k ) , also necessitates i m p r o v e -m e n t of a n a l y t i c a l t o o l s t o a c c o u n t f o r t h e r e -m a i n i n g scale effects. C o n s e q u e n t l y , in t h e t h e o r e t i c a l w o r k o n p r o p u l s i o n h y d r o d y n a m i c s , t h e search f o r t h e
e x p l a n a t i o n of scale effects receives i n c r e a s i n g a t t e n t i o n .
T o t h e already e x i s t i n g c a l c u l a t i o n p r o g r a m s for q u a s i s t e a d y loads a n d c a v i t a -t i o n a n d f o r u n s -t e a d y loads a n d v i b r a -t i o n , a p r o g r a m for -t h e v e l o c i -t y f i e l d in -t h e w a k e has been a d d e d . The f i n a l a i m of t h e latter p r o g r a m is t o p r e d i c t t h e e f f e c t i v e w a k e d i s t r i b u t i o n in t h e propeller plane of a s h i p , needed in t h e d e s i g n of w a k e a d a p t e d p r o p e l l e r s , u s i n g t h e n o m i n a l w a k e measured b e h i n d a m o d e l as starting p o i n t . For t h a t p u r p o s e t w o d i s t i n c t steps are n e e d e d , viz. a scale effect c o r r e c t i o n t o o b t a i n t h e n o m i n a l w a k e f i e l d of t h e actual s h i p a n d t h e p r e d i c t i o n of t h e d i f f e r e n c e b e t w e e n n o m i n a l a n d effective w a k e . W i t h regard t o t h e scale e f f e c t a m e t h o d is i n t r o d u c e d , based o n a t h r e e f o l d c o n t r a c t i o n of t h e m o d e l n o m i n a l w a k e f i e l d i n d e p e n d e n c y of its h a r m o n i c s c o n t e n t . A p p l i c a t i o n t o t w o g e o s i m series s h o w s p r o m i s i n g results. M u c h e f f o r t w i l l n o w be g i v e n t o t h e s e c o n d step, viz. t h e p r e d i c t i o n p r o c e d u r e . In t h e c a l c u l a t i o n p r o g r a m o n q u a s i - s t e a d y loads a n d c a v i t a t i o n , w h i c h is s u i t a b l e f o r t h e analysis of a propeller in a n o m i n a l w a k e f i e l d , t h e e f f e c t s of b o u n d a r y layer p h e n o m e n a o n t h e propeller blades are t a k e n i n t o a c c o u n t . This feature f a c i l i t a t e s t h e s t u d y of t h e e f f e c t of t h e R e y n o l d s n u m b e r o n t h e characteristics of t h e propeller, w h i c h is part of t h e m o d e l - s h i p c o r r e l a t i o n . T h e o r e t i c a l w o r k o n v i b r a t o r y hull pressures a n d forces has resulted in an internal report, w h i c h gives a s u r v e y of e x i s t i n g literature a n d t h e o r e t i c a l
a p p r o a c h e s . It is t h e result of a s t u d y p e r f o r m e d t o f i n d o u t w h i c h s o u n d t h e o r e t -ical base has t o be g i v e n t o t h e n u m e r i c a l a p p r o a c h , t h e d e v e l o p m e n t of w h i c h has n o w been s t a r t e d .
T h e c o m p l e t e e x p e r i m e n t a l o p e n - w a t e r data of t h e W a g e n i n g e n B - s c r e w series have n o w been c o l l e c t e d in a set of p o l y n o m i a l s . A n e x t e n s i o n t o these p o l y -n o m i a l s has bee-n m a d e t o i -n c l u d e t h e effect of R e y -n o l d s -n u m b e r .
Observed and calculated cavitation on suction side of propeller model. (Van Oossanen doctor's thesis)
S e a k e e p i n g b a s i n
A i s o in thie past year it w a s necessary t o w o r k in t h i s f a c i l i t y in d o u b l e - s h i f t s because of t h e h e a v y load of industrial orders. A p p r o x i m a t e l y 7 5 per cent of the a c t i v i t i e s c o n s i s t e d of s t u d y i n g a n d s o l v i n g p r o b l e m s f o r t h e o f f s h o r e i n d u s t r y , as f o r i n s t a n c e t h e b e h a v i o u r of p i p e - l a y i n g barges in d e e p w a t e r w a v e s in c o m b i n a t i o n w i t h t h e forces in t h e stinger a n d pipe, t h e merits of single p o i n t m o o r i n g s y s t e m s , t h e s i n k i n g a n d l a u n c h i n g of j a c k e t - t y p e p r o d u c t i o n p l a t f o r m s . T h e t r a d i t i o n a l s e a k e e p i n g e x p e r i m e n t s w e r e m a i n l y carried o u t f o r s e a g o i n g t u g - b a r g e c o m b i n a t i o n s , w h e r e special a t t e n t i o n w a s g i v e n t o t h e forces in t h e c o n n e c t i o n , a n d f o r gas a n d oil carriers. Due t o t h e increasing need f o r a larger c a p a c i t y of m e a s u r i n g c h a n n e l s , t h e existing a n a l o g u e r e c o r d i n g i n s t r u m e n t a t i o n w i l l be c h a n g e d i n t o d i g i t a l e q u i p m e n t .
It is e x p e c t e d t h a t t h e n e w r e c o r d i n g e q u i p m e n t w i l l be o p e r a t i o n a l in 1 9 7 4 . Despite of t h e heavy w o r k l o a d , a period of t i m e w a s needed f o r t h e necessary m a i n t e n a n c e of t h e b a s i n , w h i c h m a i n l y c o n s i s t e d of r e p l a c e m e n t of t h e w a v e g u i d e s .
Further a d a p t a t i o n s w i l l be m a d e in f u t u r e t o i m p r o v e a n d a d j u s t t h e e q u i p m e n t t o t h e d e v e l o p m e n t s of t h e projects.
H i g h s p e e d b a s i n
In t h i s f a c i l i t y a diversity of e x p e r i m e n t s w e r e carried o u t in c a l m w a t e r as w e l l as in w a v e s .
T h e m a j o r i t y of projects w e r e supervised by t h e staff of t h e s e a k e e p i n g b a s i n , s i n c e t h e y w e r e d i r e c t l y associated w i t h s h i p m o t i o n s a n d w i t h l a u n c h i n g a n d i n s t a l l a t i o n p r o c e d u r e s of j a c k e t - t y p e p r o d u c t i o n p l a t f o r m s in d e e p w a t e r w a v e s . In this respect f u l l use c o u l d be m a d e of t h e w a t e r d e p t h of 3.6 meters of t h i s f a c i l i t y t o meet, at a reasonable m o d e l scale, t h e ever increasing d e m a n d f o r larger w a t e r d e p t h a n d w a v e h e i g h t by t h e o f f s h o r e i n d u s t r y .
In c o - o p e r a t i o n w i t h t h e Royal D u t c h S w i m m i n g A s s o c i a t i o n a n d t h e U n i v e r s i t y of Brussels, B e l g i u m , systematic e x p e r i m e n t s are carried o u t i n t o t h e effect of b o d y shape of s w i m m e r s u p o n t h e resulting resistance a n d t h e pressure v a r i a t i o n o n t h e h a n d s d u r i n g d i f f e r e n t t y p e s of s w i m m i n g strokes. A l s o t h e c o n s u m p t i o n of o x y g e n , t o be i n f o r m e d a b o u t t h e s w i m m e r ' s physical strain, is b e i n g registered. T h e s e c o n d carriage, d e s i g n e d f o r r e a c h i n g v e l o c i t i e s of a b o u t 3 0 m / s e c . by w a t e r j e t p r o p u l s i o n is c o m p l e t e d a n d o p e r a t i o n a l . Tests are c o n d u c t e d w i t h v a r i o u s t y p e s of h y d r o f o i l s under s u p e r v i s i o n of t h e staff of t h e p r o p u l s i o n h y d r o d y n a m i c s d e p a r t m e n t .
W a v e a n d c u r r e n t b a s i n
A l t h i o u g h t h e m o s t s p e c t a c u l a r d e v e l o p m e n t s in t h e o f f s h o r e i n d u s t r y are c o n c e n t r a t e d a r o u n d t h e d e e p w a t e r s o f t h e N o r t h Sea ( w a t e r d e p t h 1 0 0 m a n d m o r e ) , a large v a r i e t y of m o d e l s t u d i e s , related t o o f f s h o r e activities in less d e e p w a t e r w e r e carried o u t in t h e w a v e a n d current laboratory d u r i n g 1 9 7 3 .
7 0 per c e n t of t h e tests c o n s i s t e d of studies c o n c e r n i n g f l o a t i n g o b j e c t s m o o r e d in e x p o s e d w a t e r s . A m o n g these f l o a t i n g o b j e c t s w e r e dredgers, p i p e l a y i n g vessels, storage barges a n d t a n k e r s , m o o r e d t o single b u o y s . The e m p h a s i s in these studies s h i f t e d s o m e w h a t f r o m t h e d e t e r m i n a t i o n of t h e feasibility a n d t h e d e s i g n of t h e m o o r i n g system itself t o w a r d s t h e detailed d e s i g n of t h e w o r k e q u i p m e n t , s u c h as s u c t i o n p i p e s , stingers a n d f l e x i b l e s u b - m a r i n e hoses. T h e i n t r o d u c t i o n of u n d e r w a t e r t e l e v i s i o n e q u i p m e n t a n d v i d e o tapes has a d d e d a n e w a n d very p r o m i s i n g d i m e n s i o n t o t h e already e x i s t i n g m e t h o d s for deter-m i n i n g t h e b e h a v i o u r of t h e v a r i o u s systedeter-ms t e s t e d .
T h e r e m a i n i n g 3 0 per c e n t of t h e tests c o n s i s t e d of i n v e s t i g a t i o n s i n t o t h e p r o b l e m s related t o t h e l a u n c h i n g of large tankers, t h e d e t e r m i n a t i o n of t h e m a n o e u v r i n g properties of n e w ships and a s t u d y o n t h e s t a b i l i t y of t h e head of t h e n o r t h e r n b r e a k w a t e r near H o o k of H o l l a n d . The latter p r o g r a m w a s s u p e r -vised by t h e H y d r a u l i c s L a b o r a t o r y in Delft.
For o u r o w n a c c o u n t , basic research w a s carried o u t o n t h e forces i n d u c e d by passing ships o n m o o r e d tankers a n d o n t h e p h e n o m e n o n of t h e s l o w l y v a r y i n g d r i f t i n g f o r c e s o n m o o r e d o b j e c t s .
S h a l l o w w a t e r b a s i n
D u r i n g t h e year 1 9 7 3 t h e f l o w of orders for t h e s h a l l o w w a t e r basin w a s satis-f a c t o r y . The a m o u n t osatis-f orders d o u b l e d in c o m p a r i s o n w i t h 1 9 7 2 .
M o s t of t h e w o r k w a s c o n n e c t e d w i t h ship h a n d l i n g and m a n o e u v r i n g p r o b l e m s in c o n f i n e d w a t e r a n d a great deal of t h e tests in this f i e l d served t o d e t e r m i n e i n p u t data f o r t h e m a n o e u v r i n g simulator. F o r t h a t p u r p o s e h y d r o d y n a m i c forces o n t h e s h i p had t o be d e t e r m i n e d as a f u n c t i o n of f o r w a r d s p e e d , rudder a n g l e , d r i f t a n g l e , n u m b e r of r e v o l u t i o n s of t h e propeller and w a t e r d e p t h . A l s o tests w e r e carried o u t t o measure t h e external forces exerted o n a s h i p by canal banks, d i s c o n t i n u i t i e s in t h e w a t e r d e p t h , a n d m e e t i n g or o v e r t a k i n g ships. A n e w d e v e l o p m e n t is t h e t e s t i n g of s e l f p r o p e l l e d d r i l l i n g rigs w i t h regard t o m a n o e u -v r a b i l i t y a n d safety in hea-vy w e a t h e r .
Orders related t o t h e M i s s i s s i p p i river t o w b o a t i n d u s t r y , a m o u n t e d t o 3 0 per c e n t of t h e t o t a l t u r n o v e r .
T h e d e m a n d f o r t h e o r e t i c a l c a l c u l a t i o n s w i t h t h e d i f f r a c t i o n t h e o r y f o r o f f s h o r e s t r u c t u r e s is g r o w i n g . A lot of c a l c u l a t i o n s w e r e p e r f o r m e d o n t h e w a v e l o a d s o n large f i x e d s t r u c t u r e s a n d t h e m o t i o n s in w a v e s of f l o a t i n g structures, m o s t l y g r a v i t y structures d u r i n g t o w i n g .
D u r i n g t h e year u n d e r r e v i e w 5 per cent of t h e t u r n o v e r of this d e p a r t m e n t c o n s i s t e d of c o m p u t e r c a l c u l a t i o n s a n d associated a d v i s o r y w o r k . T h e p a r t i c i p a -t i o n in an e v a l u a -t i o n -t e a m f o r g r a v i -t y p l a -t f o r m s of -t h e Ins-ti-tu-te T N O for B u i l d i n g M a t e r i a l s a n d B u i l d i n g Structures has c o n t r i b u t e d t o t h i s d e v e l o p m e n t . For a c c o u n t of o u r o w n research, t h e f o l l o w i n g e x p e r i m e n t a l p r o g r a m s w e r e carried o u t : - d e t e r m i n a t i o n of t h e h y d r o d y n a m i c c o e f f i c i e n t s of a large t a n k e r in s h a l l o w w a t e r by means of f o r c e d o s c i l l a t i o n tests. - d e t e r m i n a t i o n of t h e f e n d e r loads d u r i n g t h e b e r t h i n g m a n o e u v r e of a large t a n k e r t o a j e t t y .
- a d d i t i o n a l m e a s u r e m e n t s of w a v e forces o n vertical cylinders t o c o m p l e t e t h e set of e x p e r i m e n t a l data gathered in t h e previous years.
A l l these test p r o g r a m s served t o c o m p l e m e n t or verify t h e o r e t i c a l w o r k . The results of t h e a b o v e m e n t i o n e d i n v e s t i g a t i o n s w i l l be p u b l i s h e d s o o n . In v i e w of t h e order s i t u a t i o n at t h e e n d of t h e year t h e prospects f o r 1 9 7 4 are e n c o u r a g i n g .
M a n o e u v r i n g s i m u l a t o r
D u r i n g t h e year 1 9 7 3 w o r k in t h e m a n o e u v r i n g s i m u l a t o r has c o n t i n u e d t h e d e v e l o p m e n t of t h e past years. M o r e t r a i n i n g courses w e r e c o n d u c t e d w h i l e t h e t r a i n i n g c o u l d be i n t e n s i f i e d by t h e use of t h e n e w radar s i m u l a t o r a n d t h e a d d i t i o n of m a t h e m a t i c a l m o d e l s of more ships.
T h e industrial research s h o w e d a d e v e l o p m e n t in b o t h t h e variety as w e l l as t h e c o m p l e x i t y of t h e p r o b l e m s t o be analysed. This research c o v e r e d first of all matters c o n c e r n i n g n a v i g a t i o n a l aids like t h e o p t i m a l f o r m t o present i n f o r m a t i o n a n d t h e c o n t e n t s of t h e i n f o r m a t i o n . The skill of t h e s h i p s ' staffs a n d t h e level of t h e i r t r a i n i n g in t h e use of t h e i n s t r u m e n t a t i o n p r o v e d t o have a t r e m e n d o u s i n f l u e n c e o n t h e i r p e r f o r m a n c e . This i n f l u e n c e a n d t h e items m e n t i o n e d a b o v e have a very c o m p l e x relation t o t h e p e r f o r m a n c e of m a n o e u v r e s . This p o i n t e d t o t h e need t o g a i n m o r e i n s i g h t in t h e w a y s h i p s ' staffs use t h e perceived i n f o r m a -t i o n a n d process i-t -t o s-teer -t h e ships. Therefore -t i m e had -t o be reserved -t o p e r f o r m o w n research t o investigate basic steering tasks like k e e p i n g a s h i p o n c o u r s e a n d s a i l i n g a s h i p in a s t r a i g h t c h a n n e l . Results of these studies w e r e presented at t h e N S M B - s y m p o s i u m o n s h i p h a n d l i n g . In t h e f u t u r e t h i s t y p e of research w i l l have t o be e x t e n d e d in order t o remain capable of serving o u r c u s t o m e r s w i t h t h e m o s t e f f i c i e n t research p r o g r a m s .
T o c o p e w i t h t h e increased a m o u n t of w o r k , t h e staff of t h e s i m u l a t o r w a s e x t e n d e d w i t h o n e n a u t i c a l expert, o n e p s y c h o l o g i s t specialized in e r g o n o m i c s a n d o n e c r a f t s m a n .
Parallel w i t h t h e s e d e v e l o p m e n t s broad a t t e n t i o n has been paid t o t h e prepara-t i o n of s o f prepara-t w a r e in prepara-t h e field of prepara-t h e p r o g r a m m i n g of prepara-t h e c o m p u prepara-t e r a n d processing of registrations m a d e d u r i n g t h e e x p e r i m e n t s . Vital c o m p o n e n t s in this w o r k are t h e three n e w d i g i t a l tape u n i t s , o n e t o make registrations, t h e o t h e r t w o as aids t o c o m p i l e t h e c o m p u t e r p r o g r a m s . S u b s t a n t i a l s a v i n g in p r e p a r a t i o n t i m e c o u l d be a c h i e v e d .
A s a result of these a c h i e v e m e n t s t h e s i m u l a t o r is n o w f u l l y e q u i p p e d t o meet t h e r e q u i r e m e n t s of t h e f u t u r e .
C o m p u t e r c e n t r e General T h e w o r k l o a d of c o m p u t e r a n d d r a w i n g m a c h i n e s has been h i g h d u r i n g 1 9 7 3 . A s m e n t i o n e d in t h e 1 9 7 2 A n n u a l Report t h e c a p a c i t y of t h e C D C 3 3 0 0 system has g r a d u a l l y b e c o m e i n s u f f i c i e n t t o meet t h e N S M B d e m a n d f o r c o m p u t i n g f a c i l i t i e s . Therefore p r e p a r a t i o n s started f o r t h e i n s t a l l a t i o n of P D P 11 / 4 5 a n d 1 1 / 1 0 c o m p u t e r s y s t e m s . These systems w i l l be m a i n l y used f o r t h e p r o c e s s i n g of l a b o r a t o r y r e c o r d i n g s , a n d w i l l serve as a b a t c h terminal on a C D C 6 6 0 0 c o m p u t e r . T h e t e r m i n a l f u n c t i o n w a s already installed in A u g u s t , a n d created n e w possibilities f o r large a p p l i c a t i o n p r o g r a m s .
T h e t u r n - a r o u n d of c o m p u t e r p r o g r a m s at t h e C D C 3 3 0 0 w a s g r e a t l y i m p r o v e d by t h e i m p l e m e n t a t i o n of an a u t o m a t i c a c c o u n t i n g s y s t e m , d e v e l o p e d by t h e c o m p u t e r c e n t r e staff.
A s t h e a u t o m a t i o n of v a r i o u s activities at N S M B is c o n t i n u i n g , t h e w o r k l o a d of t h e staff of t h e c o m p u t e r centre keeps increasing. T h e present s i t u a t i o n , w h e r e three d i f f e r e n t c o m p u t e r systems are used, w i l l be a t e m p o r a r y o n e . It is e s t i m a -t e d , -t h a -t in -t w o years -t i m e -t h e i n s -t a l l a -t i o n of o n e large cen-tral c o m p u -t e r w i l l be j u s t i f i e d .
Software development
S o m e of t h e e x i s t i n g p r o g r a m s f o r t h e s h i p b u i l d i n g i n d u s t r y are u p g r a d e d a n d m o d i f i e d m a i n l y in t h e f i e l d of t h e p r o g r a m o r g a n i z a t i o n t o be able t o c o p e w i t h the p r o b l e m s of s h o r t delivery t i m e s t o g e t h e r w i t h an increasing n u m b e r of c u s t o m e r s at t h e same t i m e .
The n e w p a c k a g e f o r t h e f a i r i n g of ship hull f o r m s has been c o m p l e t e d . P r o d u c -t i o n w i -t h -t h i s p r o g r a m has been s-tar-ted f o r -t h e f a b r i c a -t i o n of d r a w i n g s f o r s h i p m o d e l s . A f t e r s o m e f u r t h e r e x p e r i e n c e is g a i n e d t h e p r o g r a m w i l l be released for t h e use of o u r c u s t o m e r s .
T h e d e m a n d s f o r m o r e a u t o m a t i o n f r o m t h e laboratories as w e l l as f r o m t h e d r a w i n g o f f i c e s of t h e N S M B are i n c r e a s i n g . S o f t w a r e systems f o r t h e p r o c e s -s i n g of data f r o m t h e depre-s-surized t o w i n g t a n k and t h e m a n o e u v r i n g -s i m u l a t o r are b e i n g d e v e l o p e d .
S o f t w a r e d e v e l o p m e n t f o r t h e P D P 1 1 / 4 5 a n d PDP 1 1 / 1 0 c o m p u t e r systems w h i c h w i l l be i n s t a l l e d in 1 9 7 4 has already been i n i t i a t e d .
Shipyard production programs
O n c e a g a i n t h e largest g r o w t h w a s f o u n d in t h e N A L S - s u i t e of p r o g r a m s f o r t h e n u m e r i c a l c o n t r o l of f l a m e c u t t i n g m a c h i n e .
T h e q u a l i t y of t h e f u l l scale t e m p l a t e s d r a w n by t h e large paper t a p e c o n t r o l l e d KV 1 8 9 0 d r a w i n g m a c h i n e i n d u c e d more m e d i u m sized s h i p y a r d s t o use t h e N S M B c o m p u t e r p r o g r a m s for shell plate e x p a n s i o n a n d f o r c o d i n g of internal c o n s t r u c t i o n a l s h i p plates. C o d i n g p r o g r a m m e r s w r i t e p r o g r a m s at these m e d i u m sized s h i p y a r d s as if these w e r e in t h e possession of h i g h q u a l i t y n u m e r i c a l l y c o n t r o l l e d f l a m e c u t t i n g m a c h i n e s . T h r o u g h t h e use of t h e N A L S p r o g r a m s , all g r o u p e d a r o u n d a data base c o n t a i n i n g t h e ship's o f f s e t s , a c o n s i s t e n c y in data is a c h i e v e d . T h i s , c o u p l e d w i t h t h e increased a c c u r a c y of t h e t e m p l a t e s , ensures a h i g h q u a l i t y of d i m e n s i o n a l a c c u r a c y w i t h an associated decrease of b u i l d i n g costs.
This m a n n e r of u s i n g n u m e r i c a l c o n t r o l by small a n d m e d i u m sized yards is u n i q u e in t h e w o r l d . A n o t h e r D u t c h s h i p y a r d d e c i d e d t o use t h e N A L S system f o r its r e c e n t l y i n s t a l l e d n u m e r i c a l l y c o n t r o l l e d f l a m e c u t t i n g m a c h i n e , w h i l s t several others have m a d e enquiries f o r their f l a m e cutters d u e f o r i n s t a l l a t i o n in 1 9 7 4 .
In an e f f o r t t o speed up p a p e r - t a p e p r e p a r a t i o n , a t e l e t y p e - l i n k w i t h a s h i p y a r d has been e s t a b l i s h e d using o r d i n a r y t e l e p h o n e lines. Paper tapes are o f f - l i n e prepared a n d t h e c o d e d parts are f e d i n t o t h e c o m p u t e r . A f t e r p r o c e s s i n g t h e parts a n d t h e n e s t i n g c o d i n g s , t h e f i n a l paper tape is verified o n t h e N S M B d r a w i n g m a c h i n e a n d o n c e a g a i n t r a n s m i t t e d t o the y a r d . C h e c k i n g at t h e yard is o n l y d o n e t o ensure t h a t t h e tape is free f r o m t r a n s m i s s i o n errors.
Instrumentation
A s in t h e year b e f o r e , t h e i n s t r u m e n t a t i o n d e p a r t m e n t has spent a lot of t i m e t o i m p r o v e the o p e r a t i o n a l properties of t h e depressurized t o w i n g t a n k . Especially the remote h a n d l i n g of t h e ship m o d e l s in v a c u u m has been i m p r o v e d by replacing t h e o r i g i n a l telescopic beam c o n s t r u c t i o n by a m o n o r a i l c o n s t r u c t i o n . The t e n d e n c y , started in t h e years before, t o more a n d more c o m p l i c a t e d m e a -surements, has c o n t i n u e d in 1 9 7 3 . This a g a i n asked for a d v a n c e d apparatus w i t h very g o o d properties a n d of h i g h q u a l i t y .
In 1 9 7 3 three c o m p l i c a t e d measurements o u t s i d e the N S M B have been prepared viz. o b s e r v a t i o n of c a v i t a t i o n p h e n o m e n a o n a t w i n s c r e w high p o w e r e d c o n -tainer vessel, m e a s u r e m e n t s on board of a dredger and w a v e h e i g h t measure-ments d u r i n g t h e l a u n c h of a large tanker.
Personnel
T h e c h a n g e s in t h e staff can be seen f r o m t h e t a b l e b e l o w :
1 9 7 1 1 9 7 2 1 9 7 3 M a n a g e m e n t 6 5 5 U n i v e r s i t y g r a d u a t e s 3 3 3 3 3 8 C o l l e g e g r a d u a t e s 3 5 3 2 3 2 T e c h n i c i a n s 2 1 6 2 1 1 2 3 4 Clerical staff 2 6 2 3 2 5 Other personnel 21 19 21 T o t a l 3 3 7 3 2 3 3 5 5
Publications, lectures, meetings
T h e f o l l o w i n g p u b l i c a t i o n s w e r e i s s u e d (the n u m b e r s m a r k e d w i t h * w e r e p a p e r s ) No. Title 3 6 9 * Profile characteristics in cavitating and n o n -cavitating f l o w s 3 9 2 * Non-conventional propulsion devices 3 9 3 * The N S M B - 4 0 years ofscientific industrial service in marine technology 3 9 7 * The effect of cavitation on
the interaction between propeller and ship's hull
Author
P. van Oossanen
Published in
Schip en Werf, 1973, p. 3
J . D. van Manen ISP, 1973, p. 173 J . D. van Manen
J . D. van Manen
3 9 8 * Cavitation of hemispherical J . H. J . van der nosed teflon bodies Meulen
4 0 3 * Service performance and seakeeping trials on a large containership 427 Manoeuvring large ships
in shallow water - I, II 4 2 9 * A power prediction
method for motor boats 4 3 0 * Feasibility and profit of
navigation information and navigational aids offshore 431 * Some design-criteria for
offshore structures carrying sensors and monitors for the information to large vessels
432 International Jubilee Meeting on the Occasion of the 40th Anniversary of the Netherlands Ship Model Basin, The Hague and Delft, August 30 -September 1, 1972 4 3 3 * Recent developments in marine propeller G. Aertssen and M. F. van Sluijs J . P. Hooft G. van Oortmerssen J . van Dixhoorn, L. A. Koelé and J . P. Hooft L. A. Koelé and J . P. Hooft M. W. C. Oosterveld and
Int. J u b . Meet, on the Occas. of the 40th Anniv. of the N S M B , The Hague and Delft, 1972, p. 9 (1973) Proc. l U T A M Symp. on Non-Steady Flow of Water at High Speeds, Leningrad, 1 9 7 1 , p. 305 (1973) Proc. l U T A M Symp. on Non-Steady Flow of Water at High Speeds, Leningrad, 1 9 7 1 , p. 329 (1973) Trans. RINA, 1972, p. 429
J . of Nav., 1973, p. 189 and 311
Symp. Yacht Architecture '73, Amsterdam, p. 31 XXIIIrd Int. Nav. Congr., Ottawa, 1973, Sect. II -Ocean Nav., Subj. 1, p. 157 XXIIIrd Int. Nav. Congr., Ottawa, 1973, Sect. II -Ocean Nav., Subj. 3, p. 73
N S M B , Wageningen, 1973
Int. J u b . Meet, on the Occas. of the 40th Anniv. of
No. Title Author Published in 435* Retrospection on 1 5
years N S M B seakeeping activities
436* Ocean technology
437* Design and operations
4 3 8 * The mean wave, w i n d and current forces on offshore structures and their role in the design of mooring systems
439 Extended diagrams for determining the resistance and required power for single-screw ships 440* Ducted propeller
characteristics
440a Weitere Ergebnisse syste-matischer Versuche mit Düsenschrauben
441 De huidige stand van de NALS programma's ten behoeve van het numeriek sturen van brandsnij-machines
442* Influence of wake on
M. F. van Sluijs and Tan Seng Gie
J. P. Hooft J . Holtrop and A. Koops G. F. M. Remery and G . v a n Oortmerssen W. H. auf'm Keller M. W. C. Oosterveld J. D. van Manen and M. W. C. Oosterveld A. W. Ruys W . v a n Gent and P. van Oossanen
Int. J u b . Meet, on the Occas. of the 40th Anniv. of the N S M B , The Hague and Delft, 1972, p. 186 (1973) Int. J u b . Meet, on the Occas. of the 40th Anniv. of the N S M B , The Hague and
Delft, 1972, p. 218 (1973) Int. J u b . Meet, on the Occas. of the 40th Anniv. of the N S M B , The Hague and
Delft, 1972, p. 315 (1973) Fifth A n n . Offshore Techn. Conf., Houston, Texas, 1973, Vol. I, p. 169 ISP, 1973, p. 133
Proc. Symp. on Ducted Propellers, Teddington, 1973, p. 35
Schiffstechnik, 1973, p. 35
Schip en Werf, 1973, p.260
Second Lips Propeller Symp., Drunen, 1973,
No. Title
448 Netherlands Ship Model Basin
449 Het computerprogramma Stabcrit van het reken-centrum van het NSP
Author Published in
N S M B , Wageningen, 1973 H. Konijnenberg Schip en Werf, 1973, p. 454
B e s i d e s t h e p u b l i c a t i o n s m e n t i o n e d b e f o r e , t h e f o l l o w i n g l e c t u r e s w e r e g i v e n i n 1973
Date Subject June 7
Cavitatie-onder-zo6l< bij het Ne-derlands Scheeps-b o u w k u n d i g Proefstation Author J . H. J . van der Meulen
September 4 Research activities M. W. C.
at the N S M B Oosterveld September 6 October 3 Ship-model corre-lation allowances Ducted propellers Hydrodynamic aspects of offshore gravity structures J . J . Muntjewerf M. W. C. Oosterveld G. van Oortmerssen October 3 October 24 Surface charac-teristics and cavitation inception Scheepsbouw en J . H. J . van der Meulen J . D. van Manen Audience Wetenschappelijke bijeenkomst gewijd aan 'Cavitatiegeluid' at Wageningen, organized by 'Nederlands Akoestisch Genootschap' Department of Naval Architecture of the Faculty of Engineering of the Hiroshima University in Hiroshima
Nagasaki Technical Institute of Mitsubishi Heavy Industries, Ltd. in Nagasaki
'Afdeling voor Onder-watertechniek, Sectie voor Grondmechanica en Funderingstechniek van het Koninklijk Instituut van Ingenieurs' and Netherlands Section of the Society of Petroleum Engineers of the A I M E in The Hague EUROMECH 4 5 : 'The Mechanical Properties of Interfaces between T w o Fluids' in Palermo Scheepsbouwdag 'Appel aan de scheepsbouw' in
Date Subject Author Audience November 2 9 - 3 0 Influences of the water depth on the manoeuvring characteristics of ships Analysis and training of ship handling capabil-ities G. van Oortmerssen P. J . Paymans and K. Meurs Symposium on 'Ship Handling' at Wageningen, organized by the Nether-lands Ship Model Basin
December 11 December 14 Statistical analysis of ship's manoeuvres The influence of the human behaviour on the c o n -trollability of ships Schokgolven in mengsels van vloeistoffen en gasbellen I. Oldenkamp J . P. Hooft L. Noordzij U.S.Coast Guard Headquarters in Washington
'Sectie voor Mechanica van het Koninklijk Instituut van Ingenieurs' at Delft
T h e f o l l o w i n g m e e t i n g s w e r e a t t e n d e d In 1973 January 1 1 - 1 2 February 20 February 23 February 2 7 - 2 8 March 6 - 8 March 21 March 30 April 3 0 - M a y 2
Symposium 'Moderne computer-technologie en architectuur' at
Enschede, organized by 'Neder-lands Rekenmachine Genootschap en Sectie voor Telecommunicatie-techniek van het Koninklijk Instituut van Ingenieurs'
'Offshore'-day at Delft, organized by 'Sectie voor Scheepstechniek van het Koninklijk Instituut van Ingenieurs en Nederlandse Vereniging van Technici op Scheepvaartgebied'
W. Verschuur and A. de J o n g
Meeting of S N A M E Panel H-10 (Controllability) in New York ITTC Seakeeping Committee at St. Albans
Course on Fundamentals of Data Communications in London, organized by Infotech Ltd. Symposium Yacht Architecture '73 in Amsterdam.
Third symposium on developments of interest to yacht architecture, under the auspices of the HISWA, Netherlands Association for Trade and Industry in the field of Shipbuilding and Aquatic Sports Meeting of S N A M E Panel H-10 (Controllability) in Washington Fifth Annual Offshore Technology
J . D. van Manen, J . P. Hooft, M. W. C. Oosterveld, L. J . Boreel, H. L. Minkenberg, G. van Oortmerssen, G. F. M. Remery and M, F. van Sluijs P. Hooft J . M. F. van Sluijs A . W . Ruys J . J . Muntjewerf and G. van Oortmerssen J . P. Hooft
G. van Oortmerssen and G. F. M. Remery
May 3 0 - J u n e 1 June 4—5 June 4 - 5 June 4 - 8 June 7 June 2 0 - 2 2 J u l y 9 - 1 8 J u l y 27 August 2 8 - 3 0 September 2 0 - 2 1 September 21 October 1-3 October 2 - 4
Symposium on Ducted Propellers at Teddington, organized by the Royal Institution of Naval Architects
ITTC Propeller Committee in Newcastle upon Tyne ITTC Cavitation Committee in Newcastle upon Tyne 5th International Congress on Ergonomics in Amsterdam, organized by 'Nederlandse Vereniging voor Ergonomie' Wetenschappelijke bijeenkomst gewijd aan 'Cavitatiegeluid' at Wageningen, organized by 'Nederlands Akoestisch Genootschap'
Joint Meeting of Fluids Engineer-ing and Applied Mechanics Divisions of the American Society of Mechanical Engineers in Atlanta, Georgia
XXIIIrd International Navigation Congress in Ottawa, organized by the Permanent International Association of Navigation Congresses
Meeting of S N A M E Panel H-10 (Controllability) in New York International Conference on Computer Applications in the Automation of Shipyard Operation and Ship Design in Tokyo, co-sponsored by International Federation for Information Processing, International Federa-tion of Automatic Control, and Society of Naval Architects of Japan
ITTC Performance Committee at Trondheim
Meeting of S N A M E Panel H-10 (Controllability) in New York EUROMECH 4 5 : 'The Mechanical Properties of Interfaces between Two Fluids' in Palermo
International Congress of the
J . D. van Manen and M. W. C. Oosterveld
M. W. C. Oosterveld P. van Oossanen P. J . Paymans
J . H. J . van der Meulen
J . H. J . van der Meulen
K. Meurs J . P. Hooft J . J . Muntjewerf and M. W. C. Oosterveld J . J . Muntjewerf J . P. Hooft
October 30
November 1 5 - 1 6
November 23
November 2 8 - 3 0
Naiaarsconferentie van de Sectie A. W. Ruys voor Bedrijfsorganisatie van het
Koninl<lijl< Instituut van Ingenieurs at Lunteren
Eighty-first Annual Meeting of the Society of Naval Architects and Marine Engineers in New York Symposium on the occasion of the 70th anniversary of the Society of Students in Naval Architecture 'William Froude' at Delft
Symposium on 'Ship Handling' at Wageningen, organized by the Netherlands Ship Model Basin
J . D. van Manen and M. W. C. Oosterveld J . D. van Manen
December 14 Meeting of S N A M E Panel H-10 (Controllability) in New York
J . D. van Manen, M. W. C. Oosterveld, J . P. Hooft J . J . Muntjewerf, A. H. Pastoor, K. Meurs, I. Oldenkamp, G. van Oortmerssen and P. J . Paymans J . P. Hooft
O r g a n i z a t i o n s c l i e m e and principal p e r s o n n e l of t h e NSIVIB
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 . Muntjewerf 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 . Muntjewerf 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 personne!
J . F. Meijer General secretariate F. W. J . van Bochoven J . Kools Maintenance section Domestic section Planning and information
Deep water towing tank
A . J o n k
M. P. van der Veen R. Sellmeijer
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
Depressurized towing tank
G. Kuiper W. van den Berg J . Holtrop M. Hoekstra S. van de Brand Computer centre Hardware control W. Verschuur A. de Jong
Wave and current basin
G. F. M. Remery J . A. Pinkster J . E. W. Wichers Seakeeping basin M. F. van Sluijs H. L. Minkenberg J . J . Blok H. Rijken C. Flokstra
