Latz, p. Technjscpe. De lit. Observations made on board of. Dutch ships. June 1967

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1 Lat, p. Technjscpe De lit. Observatins made n bard f Dutch ships. June 1967

2 NETHERLANDS SHIP MODEL BASIN WAGENIN GEN Reprt N WO PAGE OBSERVATIONS MADE ON BOARD OF DUTCH SHIPS by Ir. R. Wahab.

3 NETHERLANDS SHIP MODEL BASIN WAGE NINGEN Reprt N WO PAGE Intrductin * In 1958 the Panel n Seakeeping Research f the Netherlands Ship Mdel Basin invited the Butch Shipping Cmpanies t intrduce a "Jurnal n ship behaviur at sea" abard their ships. By intrducing this Jurnal it as tried t btain an insight int the flling aspects: - the respnse f the ship t the sea and ind - the reactins f the ship's staff n the behaviur f the ship - the state f the sea as a functin f lcatin, time and ther circumstances. * The Panel cmprises representatives f: shipping cmpanies, shipyards, the Technlgical University f Deift, the Hydraulics Labratry and the Netherlands Ship Mdel Basin.

2. The cllecting f the data The bservatins entered

The captaina f the ships ere advised t use the

Nt all f the data btained in this manner have a high

It as expected, hever, that this lack f accuracy

bservatins. Every bservatin cnsists f 34 data.

necessary t use mechanical means fr their digestin.

4 NETHERLANDS SHIP MODEL BASIN WAGEN IN GEN Reprt N WO PAGE The cllecting f the data The bservatins entered in the Jurnal ere made ith the instruments nrmally available n bard a ship. Partly the data ere btained by visual bservatin. The captaina f the ships ere advised t use the Jurnal tice a day. Nt all f the data btained in this manner have a high degree f accuracy. It as expected, hever, that this lack f accuracy night the cmpensated by the large number f bservatins. Every bservatin cnsists f 34 data. The large number f data thus btained made it necessary t use mechanical means fr their digestin. Fr this reasn all bservatins ere cded in igures. Beteen 1959 and ,000 bservatins have been made n bard f 243 ships, representing abut 40 per cent f the Dutch merchant navy. Figure 1 gives the sie f these ships.

NETHERLANDS SHIP MODEL BASIN WAGENIN GEN Reprt N. 67-090-WO PAGE 3.

the rather cmplicated cherence amng them made it necessary t perfrm the

the sea and n the cnditins hich may make the captain decide t change curse

The ccurrence f chanre f curse and/r speed reductin In adverse eather the

certain unifrmity, the quantities in hich these reactins are expressed may

In the Tables I and II the number f times speed as reduced r curse as

It is cnspicuus that n the Nrth Atlantic ships f i-00-500 feet length had

300-350 feet length had the largest difficulties.

curse r t sl dn is given in Figures 2 and 3.

5 NETHERLANDS SHIP MODEL BASIN WAGENIN GEN Reprt N WO PAGE The analysis f the bservatins The large number f bserved quantities and the rather cmplicated cherence amng them made it necessary t perfrm the analysis in stages; every next stage being strngly dependent n the results f the previus ne. At present a first analysis has been made f the bservatins n the state f the sea and n the cnditins hich may make the captain decide t change curse r decrease speed. The ccurrence f chanre f curse and/r speed reductin In adverse eather the captain may decide t change curse, t decrease speed r t d bth t reduce the severity f the ship's behaviur. Assuming that the reactins f the nautical fficers f the varius ships sh a certain unifrmity, the quantities in hich these reactins are expressed may be treated in the same ay as the purely physical behaviur f the ship. In the Tables I and II the number f times speed as reduced r curse as changed is given. It is cnspicuus that n the Nrth Atlantic ships f i feet length had t sl dn r change curse mst ften hile n the Indian Ocean the ships f feet length had the largest difficulties. The arguments advanced by the nautical staff fr their decisin t change curse r t sl dn is given in Figures 2 and 3. In the Figures the number f times every argument as used is given as a percentage f the ttal number f bservatins invlved. In mst cases a cmbinatin f causes as put frard. Therefre the sum f the percentages exceeds 100. As culd be expected the ccurrence f phenmena like shipping ater, siaimmiing etc, hich are cnnected t the lngitudinal ship mtins generally lead t a speed reductin.

functin f the bserved ave height in Figure 4.

attained 'by these ships is abut ne-third ler than in calm seas.

height f the sell crrespnds very ell ith the bservatins cllected

Figure 6 indicates that the variance f the bserved ave height in

Figure 7 als suggests that the aves hich have been designated by

cnsidering the ave height, since the bservatins taken n bard f

6 NETHERLANDS SHIP MODEL BASIN WAGEN INGEN Reprt N. 67-O9O-WO PAGE LI-. Severe rlling leads mstly t a cha.nge f curse. Fr ne ship type,victry ships,the mean speed is given as a functin f the bserved ave height in Figure 4. This Figure shs that in severe head seas the average speed attained 'by these ships is abut ne-third ler than in calm seas. Sea and ind cnditins Figure 5 indicates that the mean bserved height f the sell crrespnds very ell ith the bservatins cllected by Rll [i]. This is cntrt the ind aves. Figure 6 indicates that the variance f the bserved ave height in nt significantly different fr ind aves r fr a sell. Figure 7 als suggests that the aves hich have been designated by the bservers as sell crrespnd t the bservatins f ther investigatrs. Hever, Figure 8, indicates that ne shuld be very careful in cnsidering the ave height, since the bservatins taken n bard f small ships clearly differ frm thse taken n large ships. Frm the abve it nay be cncluded that it is very difficult t find a single parameter hich represents the character f the sea sufficiently accurate t serve as a basis fr a further analysis f the data n the behaviur f ships at sea.

7 NETHERLANDS SHIP MODEL BASIN WAGENNGEN Reprt N WO PAGE Cncluding remark The digestin f the data has cnsumed much time and. is expected t cnsume much mre. Only a selectin f are presented here. It is hped that the first results [4] in the near future a much mre extensive reprt can be presented, hich may cntribute t a clearer insight int the behaviur f a ship at sea.

NETHERLANDS SHIP MODEL BASIN WAGEN INGEN Reprt

: Die Grasse der Meeres ellen in Abhngigheit

Statistics f ave heights and perids fr the

David Taylr Mdel Basin, Reprt 1091, September

8 NETHERLANDS SHIP MODEL BASIN WAGEN INGEN Reprt N WO PAGE 6. References : Rll, H.U.: Die Grasse der Meeres ellen in Abhngigheit vn der Windstärke. Einelveröffentlichung Nr. 6, Deutscher Wetterdienst, Seeetteramt, Hamburg : Brks, R.L. and N.H. Jasper: Statistics f ave heights and perids fr the Nrth Atlantic Ocean. David Taylr Mdel Basin, Reprt 1091, September : Reprt f Cmmittee N. I n envirnmental cnditins. Prceedings f the Internatinal Ship Structures Cngress, July Stijninan J.J.: Eerste uiterking van het Jurnaal gedrag in eegang. Reprt N WO f the Netherlands Ship Mdel Basin, Wageninen, The Netherlands.

9 TABLE I Observatins ith change f curse and / r speed reductin I II III Cmbined speed- Speedreductin Ttal Shiplength Speedreductin Change f curse reductin + change and / r change number f f curse f curse bservatins nunber percentage ximber percertage number percentage numrpernte 300,-350' I2 4-00' -450' e _550} '-750' 3S2S C-) i '-350' ' -450' Z 5001_550t} , ' - 750'.33 y Z 300' -350' ' -450' p' Z si_550t} '-750' m-4 Im,- > >0 øv, r!, V! '.

10 TA13TE II - Change f curse and / r speed reductin n the Nrth Atlantic. I II III Speed reductin Change f curse Cmbined speed reductin + change f curse Speed reductin and / r change f curse number percentage number percentage number percentage number percentage East bund West bund TtJ. number f bservatins hi c-p s.'

67-090-WO TABLE III - Change f curse and

Head seas (ave directin I, see Figure 4.

50 0 0 0 0 0 0 0 0 90 4.50-6.00 2 0.5 1 0.

6 0 0 3 16 191 7.20-8.70 2 0.5 9 2.5 1 0.

11 NETHERlANDS SHIP MODEL BASIN WAGENINGEN Reprt N WO TABLE III - Change f curse and I r speed reductin f Victry ships. Head seas (ave directin I, see Figure 4.) Draft frard (in) I II III I + II + III speed reductin change f curse cmbined speed reductin + change f curse speed reductin and / r change f curse number percentage number percentage number percentage number percente Ll O I 5 7 O Ttal number f bservatins B seas (ave directin II, see Figure ii-.) e Beam seas (ave directin III, see Figure 14.) Quìrtering seas (ave directir. IV, see Figure 4.) Flling seas (ave directin V, see Figure 4.) I 27 O O 0 I i PAGE 9.

12 TANKERS OTHER SHIPS SHtP LENGTH in ft FIG. i

13 300ft.< SHIP LENGTH <350 ft. 8,7L.2 OBSERVATIONS 50 CHANGE OF COURSE ANO SPEED 33 OBSERVATIONS CHANGE OF COURSE 50 OBSERVATIONS e- W (J W Q- 50 SPEED REDUCTION 122 OBSERVATIONS 25 (D (D (D Z Q- ZW (D L) e-- - L) - I- > t O W Q W W W W LL (D< 0-1W WO FI G. 2

14 - SHIP LENGTH > 500 ft OBSERVATIONS 50 CHANGE OF COURSE ANO SPEED 36 OBSERVATIONS 25 r i () 50 CHANGE OF COURSE 18 OBSERVATIONS a: SPEED REDUCTION 129 OBSERVATIONS 25 -J -J IL) IL) Q U) I- Q- a: u (-n 0 a: I a: a: D > u- U) 00 a: Q- L) a: a: L) a: I- 4 u- a: I- 4 LL Q- I(J) a: 4 D 4 -J u

15 VICTORY SHIPS 15 u-i C. C Q- (I) 4 10 Wave directin Wave height in m I E , 9 N HEIGHT OF SWELL in m FIG. 4

16 MEAN WAVE HEIGHT OBSERVED BY ROLL [1] NORTH ATLANTIC OCEAN 7.5 I E I.- I(D LUI LU > 4 s / / /N. MEAN OBSERVED WAVE HEIGHT SWELL MEAN OBSERVED 1/NWAVE HEIGHT WIND WA VES 2.5 s s WINOFORCE i IN BEAUFORT FIG. 5

17 100 '7/, -,4( / il s,( 3 // WI NO WAy E S I- 50 L) Q- g l III /, BEAUFORT 6 Il/i I II / i"1/ /1/ II/y BEAUFORT 3,/ / 1 / BEAUFORT /' NUMBER OF OBSERVATIONS - WINOWAVES SWELL 3 14, , , I.- 5 III / // 6 SWELL Q- O OBSERVED WAVE HEIGHT in m. FIG. 6

18 9 9, I- L) LU a- 10 i // / 17/ / /' /5/ /// / / I 1 A / / ;y.4 'A / HEIGHT /'4 PERIOD /. / / I 'i' 1' s N.S.M B OBSERVATIONS 0.1MB. [2] 115,064 I.S.S. C. [3] ROLL 11) HEIGHT in m t0 PERIOD in sec FIG. 7

19 l / SHIP LENGTH >500 ft 1259O OBSERVATIONS SHIP LENGTH<350ft OBSERVATIONS 25 5Q 75 OBSERVE O HEIGHT OF SWELL in m. FIG. 8

Kinetic Model Completeness

Kinetic Model Completeness 5.68J/10.652J Spring 2003 Lecture Ntes Tuesday April 15, 2003 Kinetic Mdel Cmpleteness We say a chemical kinetic mdel is cmplete fr a particular reactin cnditin when it cntains all the species and reactins