The pitch and heave of ten ships of destroyer like form in regular head waves - computer predictions compared with model tests results

THE PITCH AlD) HEAVE OF TEN SHIPS OF DESTROYER-LIKE FORM IN REGULAR HEAD WAVES

-C4PUTER PR)IQTIONS CC*IPARED WITH MODEL TEST RESULTS

By

Peter A0 Gale

Pre]±ninary Design Branch Bureau of Ships

U.S _{Na'vy Department}

November 19614

7

Lb.

_{v. Scheepsboijwfcuncje}

Technische Hogeschool

Deift

NOTES

].. Regular wave model test results were coilecte4 for ten destroyer-like

ships. The data for five of the ships (F- K) were classified. By coIncidence, model test phase angle results were not available for these same five ships. Due to the above, data sources, ship

identi-fications and

dimensions, body plans, and phase angle comparisons are not presented for ships F K.

For ships, F and G the longitudinal 'radius of the model was not known. In order to use the computer to predict the motions of these two ships, KIp was asSumed to be O.2SL for bpth. These facts make the comparisons presented for ships F

and

G of dubious "value. The hull dimensions and coefficients presented in the Table, of Ship Particulars are those used for the computer motion calculations,: In

general they also apply to the model test hull forms. In a few cases there are minor differences between the forms model tested

and

those uped for, the motion

cQnpu'tatipns

as, for example, when the model tested did not float on an 'seven keel, Notion computations were

a].way8m for the even keel. case.

l. .In the graphs, the circles connected by lines represent

the computer calu1ations. The model test results are represented by symbols other than circle8. Ship K was model tested in regular waves of several heights and all of the test results are presented necessitating the uSe of a different ordinate than used for the other plots.,

The foUowing reports were the Sources of the model test data, for hps

A-Eg

' '

a,

For shipsAandB:

5An Experimental Study of the Effect of Extreme Variations in Proportions and Form on. Ship Model Behavior in Wave&1, by Numata and Lewis, 'ETI' Report No, 6Z.3,December 19S?.

b. For ships C, D, and E:

The Influence of Shipform arid Length on the Behavior of Destroyer-Type Ships in Head and Beam Sea&', 'by Nuntjewerf, International Shipbuilding Progress, Vol. 10, No. 102, February 1963. '

6. The, computer program used to calculate the ship motions presented here

was !ritten in the Bureau of Ships and is. based upon a theoretical method developed by Korvin-Kroukovs1y for computing the coupled pitch

computational pràcedure followed by the computer is essentially that presented

in

Davidson Laboratory Report No.

791,

"Guide to Computational Procedure for

Analytical

Evaluation of Ship Bending Ma'ients in Regular Waves", by Jacobs, Daizell, and

Lalangas dated October,

196.

The computer

program uses the Prohaska added mass coefficients dth Ursell's free surface corrections and Grimes 19S9 daiping coefficients, all published in D. L. Report No. 791. It isrecognized that it would be:more logical to use Grins. 19S9 added mass and damping coefficients or perhaps even more recent data; this was not done for several practoa]. reasons The Bureau of Ships computer program divides the hull into ten station spaces for the computations. It has been found that the uáe of. a greater number of station spaces. has a. negligible effect

oh

the computed reSults.

ma4unnri single amplitu4e of pitclxthg motion

maximum single

amplitude of

heaving motion of ship's center of gravity.

.NCLLTURE

phase lead of maXintun pitch up rneasure4 with respect to the 'instant when' the wave node' preàeding the wave crest is at the ship' a

lon4tüdinal center

of

gravity location

phase lead of maximum heave up defined as for pitch phase 'angle above0

regular wave length.

wterline length at ship..

h regular wave amplitude.

2h regular wave heigit (twice wave amplitude).

SHIP:

LWr14.

B on WL4

H

to 1L

to WL

LTSW B/H L/H _L:i1ç

0O1L3

op.

Ow LOG. ,%

L aft

Kt1j IL

Identifica ion:

Lengthened

Dutch

Dutch

Dutch DD-710 DD-.710

Node]. B Model .D

Model

B'

*1

.Assued value

A

383.0

140.50

]L00

3393

9,146 2.89 27.36 60.14 0.6147 O.145 0.5147 0.770. 2.014

0236

B _1482.3

36,00

12.714

3396

13.140 2.83 37.86 30,3 0.6147 O.14S 0.5147 0.770 2.145 0.2140 C

368.8

38.52

13.12

3017

9.57

I 2.914 28.10 60.2 0.688 0.822 .0.565

0.805

1.23

0.233

D 14142.9

35.17

12.11

3027

12.59 2.90 36.59 31&.8 0 683 0.82 0.563 0.805

1.32

0.233

E i.i142.9

1.2..i9

12.014 3014]. 10.50 3.50 36.78 35.0 0 6214 0.759 0.1473 0.791 1.14].

:0.233

10.02 3.39 314.00 lil.5 0

611

0,800

0,1489 0.7145

1.70.

0.250*

9.78 2.90 28.14]. 147.0 0.573 0.785 0.1450 0.716 2.142.

0.250*

9.10 2.96 26.92 _55.14 0.579

0792

0.1459 0.725 .

1.50

0.2140 .' J 8.21s.

3.51

29.17 61.7 0.570

O.91O

'0.519

0.717

0.88

0.235

9.90

-2.96

29.26

50.2

0.6214 0.813 0.50? .0.771 0.614

0.211

APP

dd i

dd.

.0

=0.75

SHIP

PITCH

(AMPLITUDES).

V1 KNOTS

4

a

0

=Iry

V,

KNOTS

IL.

V2i=4ao

4.0

IL

L/2k8o

1.25

L/2h1z 48.0

₆

4

4

2

2

0

IC

20

₃₀

V1 KNOTS

8

6

4

2

125

L/

₌₄₈₀

ISHIP A. HEAVE

IC

V., cors

(AMPLITUDES)

0.75

₆

L4

_48.0

4

2

0

6

ZFT

4

2

0

>/L=

1.50

L/2480

//

o

0

20

V1 KNOTS

%h=4ao

r.

0

20

30

40

V1 KNOTS

320

EDE&

280

240

360

320

f.

280

SHIP

(PHASE

0.75

L/2h....4a0

1.25

L/2

_48.0

____

-

240

20

30

40

0

V,OTS

PITCH

ANGIEs)

320

6,

280

280

320

PE

1.00

=48.0

to

ao

V1 KNOTS

= I50

.ao

4o

V,

KNOTS

40

0

Vi KNOTS

40

0

320

DE

2

240

200

160

0

tO

20

30

V1 KNOTS

160

SHIP P

HEAVE

i60

0

0

20

30

40

0

$0

20

V1 KNOTS

V,

(HOTS

PHASE ANGLES

40

320

280

200

leo

1.00

Lj

_=48.0

l20

0

$0

20

V1 KNOTS

40

I

L/,4s.o

0.75

0

2

0

X/L=

0.75

L/k= 48.0

-

-SHIP B- PITCH

0

tO

20

30

40

V,

KNOTS

(AMPLruDEs)

(.00

=48.0

tO

20

30

V1

1N0TS

to

a

.30

kN0T5

4

L/zk 48.0

4

,DEG

2

4

4

a6,FT.

2

YL= 0.75

=450

10

20- 30

V

KP4OT.S.

(AMPLrruDES)

8

6

2FT

4

0

20

\JKN0S

YL=t.25

48.0

Ix

/

KNT

V

SIIPBHEAVE

360

32

280

SHIP B

- PITCH

0.75

L/ak

_=48.0

4 4 4

200

0

tO

20

30

'IIC.NOT

(PHeSE AIIGPLES)

1.00

360

0

20

40

V,

WN0T

0

320

ÔD

(P1.isE ANGLES)

X/L 0.75

L/2480

160

0

10

20

30

V1

SHIP B.

HEAVE

320

8.

240

160

280

0

0

20

1.25

L/2kI48o

4 4

44444

40

0

I0

40

4

2

1.20

I0

SHIP C

PITCH

V KNOTS

V KNOTS

(AMPLITUDES)

a

A

'0

20

VJICNOTS

4

DEGP 7z.h. G'.

4

F

2

YL0.6

4

10

20

KNOTS

1.20

L/2k

_33.3

SHIP C

HEAVE

(AMPLITUDE5)

40

6

L/2h

_{= 444}

10

20

30

V

IN0TS

FT

4

to

ao

30

40

0

tO

20

V

KNOTS V) KNOTS

320

280

240

0

tO

20

vi

SHIP C

P11'CH,

(PHASE ANGLES)

44.4

0

E,DE

2

0

(.50

to

₃₀

V,IcNOTS

40

L/2k

_26.7

!G'.

360

320

240

SHIP C

-4EAVE

(PHASE ANGLES)

0.90

LI.

320

280

20

160

320

DE(

280

240

.20

0

10

20

V1

iicvlors

30

X/L. L50

40

72

12h

-U_

L/..267

P. tO

20

30

40

)(MOTS

40

0

10

20

0

v,

SHIP 0

PITCH

(AMPLITUDES)

6

'4

PEG.

2

tO

20

V,,Nars

1.00

Lj

4

20

V1 KNOTS

?YL=

L/2k 53.4

0

to

20

v) KNOTS

1.25

L/2k

_32.0

-tO

2

\'d

°'

,F-r..

4

0

SHIP D- HEAVE

tO

20

30

KN0S

i00

40.0

(AMPLITUDES)

6

FT

4

I0

10

_2.0

30

V, KN0S

1.25

L/k. 320

4'

0

10

20

30

d40

0

10

20

VJ KNOTS

V

KNOTS

'L= 0.75

L/k34

YL= 0.50

L/k

= 800

200

0

SHIP D

PITCH

(PHASE ANGLES)

X/L

0.75

L/ah

_{= 53.4}

320

DE

280

240

200

100

10 ₃₀

₄₀

V kNOTS

40

10

20

30

20

V, KNOTS

40

0

80

3

28.0

240

200

SHIP D

_HEAVE

(PHASE ANGLES)

X/L

0.T5

L/2534

(0

20

V

IN0TS

40

320

280

200

(60

32.0

DEG.

280

0

1.00

L/

_{= 40.0}

(0

20

30

₄₀

V1 KNOTS (0

20

V1 KNOTS

(.25

L/2k

_32.0

G. --V.

5H%P E

prrC3

(j4IPI..

8

6

2

4

L47ss

10

20

₃₀

lCNOT

=1.00

SHIP E

_HEAVE

(AMPL ITUDS)

10

20

₃₀

V1 l(NOT$

4

2

0.75

53.4-0

10

₂₀

\N0Ts

X/L125

8

L,h...32o

6

10

20

V

ICNOTS

40

40

0

320

DEl

280

240

200

0

10 _.30 VJKNOTS

5H.IP EPITcH

(PHASE ANGLES)

40

40

0

320

280

40

0

320

280.

0

44

4 4

1.25

32.0

4

0

10

20

₃₀

₄₀

VicuOTs

7L 0.TS

L/

A 4

'YLI.00

L/2400

4

80

40

0

320

290

240

200

0

tO

20

V,

KNOTS

SHIP EHEAVE

(PHASE ANGLES)

L/2hS34

40

280

0

240

1.00

Lhi =4O.0

So

V,

OTS

1.25

L/2320

to

20

30

KNOTS.

40

AlL

0.76

L/

52.7

SI4IPFPITCN

-0

(0

20

30

40

V, KNOTS

1.01

39.5

SHIP FHEPVE

10

20

30

V w.r.ors

8

6

4

'a

I0

1.0I

35

10

₂₀

V1 KNOTS

J

VL =1.26

31.7 10

20

6

4

a

0

X/L= 0.75

SkIP G

PITCk

10

20

30

KNOTS

6

DEG..

4

6

4

A/L

Q

1/zk

°

0

20

V, iworS

X/L I.ZS

L/2k

32.0

SO

20

30

'KHOTS

L/zk

53.3

:&.

>/L07S

0

0

20

30

V, KNOTS

IPcHEPVE

40

8

G

, F1

4

0

12

f0

8

6

4

2

0

10

20

V,

KNOTS

30

t

I.25

L,(2i 3.0

0

tO

20

30

40.

kNOTS

S

4

53.3

6

DEGP.

4

'4

I0

8

4

0.75

17'2k =40.0

10

20

30

KNOTS

1.25

L/2

_24.0

//

t±

0

20

IcNoTs

SH1P k

PiTCH

'a

E&.

8-X/L50

A A 10

20

30

40

V1 KNOTS

10

2.0

30

'1, KNOTS

0

0

20

KNOTS

S-1IP H

HEAVE

8

4

14

'a

a

6

4

>'/L

_(.0di

L/. 3/0

Il6

20

40

V KNOTS

/

10

20

30

V, C.NOT.S

cT0

FT.

6

1/PEG,

4

0.86

L/=4G7

SkIPJ

PITCH

4

4

DEG.

T, DEG

z

2

0

20

30

40

0

10

20

30

V INOTS

V KNOTS

X/L

143

L/

ZB.0

6

6

DE&.

xI....

I L.

L/zk 35.0

X/L_ 1.71

L/2

_Z3.

e

:0

20

30

40

0

10

20

30

40

V1 KP4ors

V1 icwoits

SHIP 5

HEAVE

0.86

L/Zk=I

467

to

aô

30

KNOTS

1Vii:: v.43

2S.0

co (0

o

0

Ox

0

'0

Q.i

(0

a

o0J

0

I

4I 4

1-0

OO

0

I

02

>.'

0

0

II

'"p

00

0

0

p.

0.8

0.6

0.4

0'

L E

ZI.4 V

10

20

30

V, KPOT

SRIP K

_.93S

HEAVE

'/L1.00/ff.

.4

?I.2s

I,*e

10.8

L.

_l.a

57.1

Ah

2.3 0

20.0 V

i0

06

40

4

.4

_V

V p V

4

4