fisheries engineering research
TRANSCRIPT
NIT-T-85-009 C3
COPV 0
CENTER FQRFISHERIES ENGINEERING
RESEARCH
A Project of the
MIT Sea Grant program
CICRAtylt; t3py' '"'"< >e!ority
hfATfONAL EA GRANT DEPOSITORYPEI L LIBRARY BUILDING
URI, NARRAGANlif.TT H.'~Y CAIMPUSNARRAQANSEt7, H I 02882
Repor t No. 8
THE EFFECT OF BULBOUS BOM RETROFITS
ON THE RESI STANCE AND SEA KEEP I NGOF k 50 METER PRESHFISH STERN TRAMLER
byClifford k. Goudey
and
Ange los D. Heli oti s
30 kpril 1985
Prepared for the Canadian Department of Fisheries and OceansHalifax, Nave Scotia
Center for Fisheries Engineering ResearchMIT Sea Grant Program
Building E38-376, 292 Main StreetCambridge, Mk 02139
MI TSG 85-15
THE EFFECT OF BULBOUS BOW RETROFITS ON THE RESISTANCEAND SEAREEPING OF A 50 HETER PRESHPISH STERN TRAQLER
Clifford A. GoudeyHIT Sea Grant Program
and-
Angslos D. HeliotisXIT Department of Ocean Engineering
Introduction:
This report describes the research conducted at NIT on bulbousbow retrofits applied to a Canadian trawler 50 meters in length.This is the third vessel in a series of three trawler hulls included
in a larger study. The results fram the other trawlers are presentedin a recent Haster' s Thesis. by Heliotis�!.
The most significant part of the thesis and this report is theship model towing tank results Experimental data and analyses aresupplemented by results from the NIT 5-D Ship Notions Program�! andresults from a resistance regression model by Holtrop�! asimplemented on computer by Sedat 4! .
The lines drawing of the 50 meter trawler�! eras provided by theCanadian Department of Pisheries and Oceans together with informationon the propulsion and aper ation of the vessel in its presentfishery. A 4. 5' model af the hull was constructed and a series of 12bulbous bow retrof i ts were prepared.
Calm water model resistance tests were conducted on the bars hulland then with each retrofitted bulb. All tests «ere done at constant
draft, i. e., the bulb configurations «ere of heavier displacementthan the original hull. The calm water results were compared and a"best" bulb was selected for seakeeping tests. The bars and bulbousmodels were teated in regular waves over a range of wave lengths atboth steaming and trawling speedsw Pitch, heave, bo» accelerations,and resistance were measured. These results are compared with the5-D program predictions.
All bulbs were fitted ta the maximum limits of the forwsr d draftand a regression model was used to explore the effects of varying thevertical bulb location. Propeller calculations were then used topredict the effect on BHP requirements based on the performance ofthe best bulb.
Model Construction
The available lines drawing included only the rater lines andbuttock lines. From these a section drawing was prepared as shown inFi gure 1.
Figure 1 Section drawing of the 50m freshfish stern tra«ler
These dra«ings «er e photographically reduced to yield an image ofS. 5' overall length. Sea Tech Znc., of Hingham, Nassachusetts «ascontracted to construct the model from clear pine using these reduceddrawings. The hull «as laminated from planks planed to the thicknessof the «atarline spacing. To allo» for ballasting, the hull ishollow but «ith a minimum «all thickness of 1. 0 inchea. i strip of0. 030" «alnut veneer «as rabbeted-in along the design «aterline.if ter sanding to specified tolerances and fairness, the hull erasfinished >ith multiple coats of marine varnish. The seal ~ ratio ofthe madel «as 35. 62 to 1..
The bulb retrofits studied «ere cylindrical with hemisphericalcaps. This geometry «as selected due to its potential economy offull-sise fabrication and reports of some success with this type ofbulb on the U. S. Nest Coast�! . The parameters varied «ere diametergar 1.>.~g~ i 1'j i brjl~q g: g '. = j *.i ' 0 «i tg >g;iq ~ ower «dge evenwith the intersection of the forward perpendicular and an extensionof the bot tom of the keel.
Thxee bulb diameters were used to cover a range of possible sixesfrom 10 to 30 percent of the midship section area. The same bulbxetrofits used during the earlier txawler experiments were used onthis model, These were 2", 3 5", and 4 5" in diameter and for thishull the actual bulb pex'centages were 9, 18 5, and 30 3,respectively, In most cases thxoughout this report, they arereferred to simply as 10, 20, and 30 percent bulbs.
The hemispherical caps «ere machined on a numerically controlledlathe from PVC round bax. Transition pieces were constructed fromPVC tubing to attach the caps to the hull. Lengthening xi ngs of G. 5,1. 0, and 1. 5 diameters «ex e prepared to allow fox variation of bulblength. Each retrofit component waa designed to be a press-fit withits neighbor, The transition pieces were accurately fitted to thehull and a thin application of silicone caulk at each joint eras allthat was needed to keep the bulbs in place and watertight. Adescription of each bulb is pxesented in Table 1. Pigures 2 thxough5 are photos of the retrofitted model during the testing.
Bulb
Description+
-7 0
7. 8 -7 0
'IO. 7 -7 0
-7 0
-2. 5
-2. 5
13. 7
11. 1
16. 3
21. 5
-2. 5
-2. 5
6 7 +Q. 4
+Q. 413. 4
20. 1 +G. 4
26. 7 +O. 4
Table 1, S peci f i cati ons of bulbs teated.
r 10$I
10$ - O.II
10$ � 1.II
10% � 1.II
20$
Is 20$ � 0.II
20$ � 1.II
20$ - 1.II
30%II
30' � 0.rIs 30%II
30% � 1.
I I I I5D
I I
ODI I
5D I I I I I f I I IQD I I I I I I I I IOD
I I5D
Percent t. Diameter I Length Fwd.' ,Submex genceof k , ' feet! , 'of' Stem ft!' , feet!
+ + +
91'594I II I
9-1I II I
9 1 i 594 II II I
9.1 I 5.94 II II
'I8. 5 I 10. 40I I
I18. 5 , '10. 40
I II
18. 5 g 10. 40II r
I8, 5 10, 40I II I
30. 5 > 13. 37I
I30. 5 I 'l3. 37
II r
30. 5 I 13- 37II I
30. 5 , '13. 37
Fi pure 2. The 20$ � 0. 5D bulb duri ng calm water tests.
Figure 5. The 20% � 0. 5D bulb during seakeeying tests.
Test Paci li ty:
The HIT Ship Nodal Towing Tank is 'l08' long, 8' 7" «ide, «ri th anor mal water depth of 4' 7! . The towing carriage is instrumentedfor resistance and motions measurements. One end of the tank is
fitted with a «rave generator while the other end has a wave absorbing"beach". Regular waves and various sea spectra can be developed,
Test Procedure:
The base hull «ras floated in the tow tank and ballasted to its
design water line. Lead billets were used and fi xed in place wi thclay. The correct displacement «as then verified by weighing theballasted model.
The towing car'riage force block «as attached to the inside of the
hull at the center of floatation, on the centerline, and in avertical position such that the force applied to the model would beapproximately in line with the location of the propeller shaft, Theforce block is designed to pivot about the pitch axis and is attachedto air-bearing heave rods to allow for vertical motions. The modelis restrained from roll, sway, ya», and surge relative to thecarriage.
The model eras towed over a range of ship speeds from 3 to 15knots. The order of speed selection was randomised and five minuteselapsed before commencing the next run or until all waves from theprevious run dissipated. The actual speeds of each run aretabularixed in Appendix A.
The procedure was repeated for each bulb retrofit. Ballast wasadded to the bow to counteract the buoyancy of the bulb. In somecases, the overall ballast arrangement had to be adjusted due to theforward location of the bulbs.
As noted in Table 'I, the top surface of the 30$ bulb was abovethe still waterline due to its sixe relative to the forward draft.At all towing speeds this bulb became submerged.
done in a similar manner except thatin the model eras done to yield a
of the model. length Runsknots an3 >, 0 knots to represent
g conditions. Wave lengths from 0, 7 toHave heights were maintained at a
The seakeeping tests werethe placement of the ballastlongi tudinsl ~~Bi ~is ~f >'.rr at'weve «iade ei ~!~i p ~yeeds ~l'reported steaming and trawlin3. 0 times LML were generated.constant 5g of the LHL,
To insure a proper transition from laminar to turbulent flow, arow of turbulence stimulators was attached to the hull 4$ of the LHLbehind the stem. These were comprised of 0. 125" diameter by 0. 062"long studs spaced 0. 25" apart. When the bulbs were attached, the roarof studs were continued in a vertical line around the transitionpiece.
Since the pitch and heave response of a trawler is clearlyaffected by the presence of the trawl gear during trawling, thiseffect was simulated during the tank tests. A parachute-type droguewith appropriate drag characteristics was towed from a point on thetransom centerline at the main deck. This was kept submerged by aweight at the junction of the tow wire and the drogue. The weightwas equivalent to the weight of two appropriately sised trawl doorsand produced a vertical «arp angle of approximatety 20 degrees. Theset-up is diagrammed in reference 1.
Pitch motions, heave motions, bow accelerations, and wave heightwere recorded duri ng each run. The accelerometer eras located on the01 deck at station 10 1/2
Calm Mater Results:
The model drag at each calm-water speed is presented in thetables of Appendix 1 together with the nondimensionalised values andthe scaled-up results. These results are presented graphically inAppendix 2 where comparisons among the various bulb lengths areincluded.
Figure 6 shows the effect of bulb sise on EHP for speeds of 10,11. 5, and 13 knots. Attempts to interpolate between the discretebulb sixes should be discouraged, however the advantage of largerbulbs at higher speeds is evident.
To demonstrate more clearly the importance of operating speed onoptimum bulb selection, the EHP changes for the three bulb diametersare presented versus speed in Fi gure 7. This reveals that the 20%bulb offers an advantage over the range of speeds above 4 knots. The10$ bulb is superior to the 20$ bulb at the lower speeds, howeverabove 10 knots its effect is diminished, becoming a detr iment above11. 5 knots. The 30$ bulb is a clear detriment at lower speeds due toits large wetted surface but offers an advantage above 11. 5 knots.Above 13 knots and beyond the range of the graph, the 30% bulb ismost beneficial.
In Figures 6 and 7, the best length bulb for each diameter isused in the comparisons. It can be seen in Appendix 2 that theeffect of length variations is more important with the 20 and 30percent bulbs Me should recall however that the length incrementsare baaed on diameter and the actual length variations of theselar ger bulbs wer e quite extreme see Table 1! .
To better visualixe the effects of length, the results of thefour 20$ bulbs are shown in Figure 8 in terms of EHP changes relativeto the bare hull. From this it can be seen that the 0. 5 D. r ing
..:-! ~ts the gree< est pote''.. i al over the speeds of int. rest. Onlyi;ice shortest ver sion offers no benefi ts over the speed range covered.
Jl
QO0
0 CY
COV! M
V O
V Q0 g 0
Figure 7
CL
bJ
O
o 'U 0 Do
4 O ms4tQ
0 0 0 0 0 0 0 0 0 0 0 0 0 00 C 40 4 hl A V. Q C 0 N PtI I I
I I I Iq[nq oU o4 pa~ealllo3 JH3
Regular wave Results:
Prom the recorded data the average pitch and accelerationresponses were determined for each regular wave length. For thecruising speed, the non-dimensionalised pitch results are shown inFigure 9. Comparing the 20$ bulb with the bare hull we can see thebulb' s apparent effectiveness in reducing pitch at wave lengths lessthan two ship lengths. Above this point the bulb seems to be adisadvantage.
2
5.0
1.8
$.7
't.5
1.5'lA
't.3
Sa 0.00.8
0.7
0.e
0.5
OA
04
0.2
0.1
0
0,4 0.6 la 1.6
Figure 9. Pitch response at a cruising speed of 11. 5 knots.
Figure 10 is a similar presentation of bow accelerations. Thesignificance of the bulb is more evident since the higher frequenciesassociated with the shorter «ave lengths are important «ith respectto accelerations and crew comf'ort.
As would be expected, the pitch response levels-off at the longerwave lengths as the vessel begins ta simply follow the slope of thewave surface. The lower frequencies in this region cause theaccelerations to diminish and !ittle difference is found with thebulb.
-11�
5-D Predictions
� � � � No Bulb
20X Bulb
Tow Tank Results
+ No Bulb
aL xo
10
OA
Figure 10. Vertical bow accelerations at 11. 5 knots.
The results at a tra«ling speed of 3. 0 knots are presented i nFigures 11 and 12. Here the effect of the bulb, if any, is notevident. The presence of the trawl-simulating drogue causes themotions to become more complicated than would occur «ith the trawleralone. The frequent coincidence of bare and bulb data suggests anunusual system response «hich is not effected by minor changes in thehull form.
Qe are unaware of any previous experiments of this type otherthan those reported in the thesis by Heliotis 1!. Tra«l interactionwith vessel motion is an area where research is obviously needed
1.9
Tow Tank Results
+I
0I
1.7+ - No BuIb
0 - 20X Bulb
1.6
1.5
1.2
Ga
o.s -l0.7 v
+ a
D.6
0.4
0.3
0.2
0.1
0
0.4 2.4 2.8'l.2 'l.5
Figure 7. Pitch response at 3. 0 knots with drogue,
DL26
>a
fD
00 OA LS 1N 1.0 2 2A LS
Fi gur e 8. Yard. i c'.aI bow accelerations at 3, 0 knots with drogue.
Added Resistance Results:
Vessel motions affect powering requirements therefore resistancemeasurements vere taken during the seakeeping tests. The results arepresented in Figures 13 and 14 in terms of non-dimensionalised addedresistance a~, defined by:
8 = Realmf' gB~ / L $ a
Figure 13 shows that in a seaway, the 20$ bulb experiences moreadded resistance than the bare hull counterpar t. However, since theresults are based on the difference between the measured resistanceand the corresponding calm-water resistance, the net effect is lessimportant since the 20$ bulb has lese resistance to begin with.
At the travling speed the results are uninterpretable due to thecomplex response caused by the drogue/vessel system. In this case,the resi stance found while towing the dr ogue in calm water is used inthe compar ison.
Fi gure 13. Added resi stance at a crui si ng speed of 11. 5 knots.
1.$
Figure 14. Added resistance at 3. 0 knots with drogue.
5-D Notions Program Results:
The NIT 5-D Shi p Notions Predicti on Programt 2! was run on thebare hull and the 20%-0. 5D bulb over a range of regular wavescomparable to the tow tank exper iments. These runs were for thecruising speed only since the program i s unable to include theef facts of a towed ob j ect,
The results are plot ted i n Figures 9, 10, and 1 3 f or comparisonwi th the experimental data. The program resul ts clearly s how thepitch damping ef f eats of the bulb retrof i t. Reasonable agreementwi th the tow tank results are found, especially i n the shorter wavelengths for pitch and the longer wave lengths for accelerations.There is some di sagreement in results for added resistance in thevi ci ni ty of the peak.
The similar trends between the experimentaL and computer res ul tsare encouragi ng. The di f f erences i n actual response values could bedue to the f act that the 5 � D program is best s ui ted for more sle ndershi ps than the one under consi deration.
Effect of Bulb Height:
Exploring experimentally the effect of bulb height was beyond thescope of this research. To gain some insight into the possibleadvantage of vertical locations other than those tested, a regressionmodel was used. The model is based on a compilation of test resultsfrom the Netherlands Ship Hodel Basin�! and an implementation in PCBASIC was obtained from Mebh Institute. The model includes bulb areaand centroid height above the baseline as parameters, It is doubtfulhowever, that it was intended for use on trawler-type hulls.
The results of a series of runs with and without bulbs arepresented in Appendix 3. Host noticahle is the underestimation ofthe 50m trawler' s resistance based on the hull description.
Comparing the bare hull with the 10$ predictions at 11. 5 knots,the relative benefits of the bulb forms are in remarkable agreementwith our experimental results. Further, we might interpret that aslight improvement could be gained hy moving this small bulb closerto the surface hy two or three feet.
The predictions for the 20$ bulb show little change from the barehull values at 11 and 12 knots. At higher speeds the bulb isbeneficial, Similarly, the 30$ hulh is of little use except at thesehigh speeds. Using 15 knot results as a guide, it seems that the5. 0' height used in the experiments is suitable. The 30$ valuessuggest that our forward dr aft limitation «as restrictive anddropping the bulb by two or three feet might be helpful.
Power Requirement Calculations:
The calm water reduction in EHP requirements with the 20$ �, 050bulb at 11. 5 knots is 52 horsepower as shown in Pigure 3. FromAppendix 2, the bare hull EHP at that speed is 600 horsepower. Thenet effect on shaft horsepower SHP! is dependent on a variety ofefficiencies and conditions which can he calculated or estimated.They are summarixed in Table 2.
The SHP reduction of the retrofit bulb depends upon the operatingregime of the engine. If the propeller turns are maintained at fullRPH the propeller efficiency changes very little and the reductionremains at 10$. If a more moderate RPN is allowed the reduced
resistance allows an improved propulsion efficiency and the netreduction in SHP of 13. 3%.
lith 20$ - 0. 5D BulbParameter Bare Hull
548600EHP
Vg
w 8!
t ~ 0. 95w
q i-t.
Qs
f rV ~ �-w! Q
h
D
R
T ~ R/ 1-t!
Kt/ J
RPN
J
P/D
p 9!
SHP
19. %2 f t/sec19, 42 ft/sec
. 2%5. 2%5
. 233
'I. 016
0. 98
1. 02
- 233
1, 016
0. 98
1. 02
14. 665 f t/sec
9. 022
15% 520 lbf
20, 230 lbf
14. 665 f t/sec
9. 022
16, 990 lbf
22, 150 lbf
1 993 slugs/ft 1. 993 slugs/ft
0. 5800. 635
200 I 150+ +
150200
0. 652
1. 090
0. 580
0. 652
1. 140
0. 560
0. II88
0. 740
0. 553
0. IIBB
0. 760
0. 550
930105II1074 975
Table 2. Power Calo ulat i ons.
Conclusions:
-17�
Gur results indicate significant reductions in SHP requirementsfor the simple bulb designs «e tested. Xt is also evident that ifthis vessel was operated at a speed/length ratio more typical oftrawlers, the benefits would be much greater. For example, Figure 8predicts EHP reductions of aver 165 horsepower �7$! at 13 knots.
The simple shaped bulbs included in thi s study are crude comparedto the car efully formed bulb commonly seen on merchant ships andnaval vessels. 'He feel that the complication of fabricating thelatter type is inconsistent with the construction practices used formost fishing vessels.
The calculations of SHP summarized in Table 2 are based on theinformation available. The wake fraction and thr ust deduction wer eestimated from data related to ship hulls. In addi tion, thepropeller efficiencies are based on 8-Ser ies data since thespecifications of the nozzle were unavailable. Propeller 8 4-85 «asassumed.
In general, the reduced propeller thr ust r equired far theretrofitted vessel at steaming speed should r esult in improvedpropulsi ve e f f i ci ency.
Since the resistance and SHP requirements are based on constantdraft rather than constant displacement, the results presented heremay be conservative. Incr eased payload due to the bulb' s volume maybe possible. Conversely, if stability conditions allow, the buoyancyof the bulb could be used to decrease the forward draf t and allowfurther resistance reductions.
-18-
References:
1. Heliotis, A. D. 1985. The Effect of Bulbous Bow Retrofits on theResistance and Seakeeping of Fishing Vessels. Thesis, HIT Dept, ofOcean Engineering, Cambridge.
2. Loukakis, T. A. 1970. Computer Aided Prediction of SeakeepingPerformance in Ship Design. HIT Dept. of Ocean Engineering Report No.70 � 3, Cambridge.
3. Holtrop, j. and G. G. J. Mermen. 1982. An Approximate PowerPrediction Method. International Shipbuilding Progress, 29: 335,
4. Sedat, R. 1984. Improving Trawler Efficiency; Part 1: HatchingHull, Engine, Reduction Gear, and Propeller. New York Sea GrantRepor't. 'Webb Institute of Naval Ar chi tecture.
5. 1980. 1: 25 Scale Hull Lines, For e Body and Af ter Body. HalifaxIndustries Ltd., Halifax, Nova Scotia.
6. Capps, J. 1983. Scalloper Turns Hidwater Trawler. NationalFisherman August 1983. Camden, Maine.
7. Abkowi tx, N. A. The Shi p Model Towi ng Tank, A Descri ption of theLaboratory. HIT Dept. of Ocean Engineering, Cambridge.
8. Comstock, J. P. 1967. Principles of Naval Architecture, SNAHE, NewYor k.
9. van Lammer en, W. P. A., J. D. van Nanen, and H, W, C. Oster veld. 1969.The Wageningen B-Scr ew Series, SNAHE Transactions.
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50 m TRAWLER WITH 10% BULBS
1' twlb wtth no ring
1800
1400
1200
10 12 14
1tN ~ wNh OJ5 Harn. Any
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14%
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10% hulh with 1 diam. ring
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Speed Knave!
1lo' bulb each 1.5 diam. any
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1400 6 8 10 12Speed Kncda!
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Speed Knots!
Speed Knote!
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f4R
50m TRAWLER WITH 207e BULBS
20% bulb with no ruing
8Ãt bulb with L5 diam. ring
8 8 10 12
r
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TNT bulb catch 1 diam. Wg
1800
1am
1000
100 12 14
5pwd Knots!
2' bulb with 14 clam. rfray
1500
LU 1400
10 12 14
20",o BULBS
Hfect of bolo ienpth on 9IP2600
No Bulb
No Ring
0.5 Dia. Ring
2400
2200
� 1.0 Dia. nina
1200
800
$2 14
Speed Knotsj
0 2 4 6 8 10
35 HlJLBS
Effect of bulb leegth oo DIP
.. NO Btdlb
No Rinq
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1.0 Dia. Ring
� 1.5 Dia. Ring
140G
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164' H!. l 1, Nc E ! lb
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16. 0
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� 16.0 1 .1C,t>! Cwp LL" B /
~ 91 . 8"' -1. 48j<
!8» 5F'/D est .
0 ~ 65VDLUHE
41446
DTA1 !. t.!
Ab! Bapp4.0
Cster ri+ .!
At Npr opsi4. O
BAR.65
est.0 «'s' ~
'.! E t s Rf Rtot al EHP
,h .I
~ JL
C.
241 +C!+! !
+C!+0+ .!+'O
+C!+O
151 8442456.21
.Zf
.Zf
.21
.Zi
+I!
+ .!+0+ t.!+ .!
.21
.21
164 ' Hul l, 10/ B l b, *. 0'
1NPUT DATA:LML T* Tf
150 16. 0
Lt:8»/-1.48
P/D est.C! 65
Ctt! t:wp.91 .8:
BhhS» 5
VDLU IE41446
est »t:stern+C!
At Nprops:h4. 0
BAR. 65
DIA
10. 0Hb Ab*.0 ' '.8
Sapp154.0
ECZ+ 1~ 50
EHPRtrRwVE t s
0Z.O
O45.O6.07 0
!~~ C.<
p !
'7C»Z 1
.21
Zf
.Zl.1
r!
~ t!«i» O4 C>
6.07.08. .!9.0
1,0. 0
1Z.AfZ.O14. 0
B. C>
9.010. 011.012. 01 'h»O
14. O0
~f48
919476956956*9777758'928
10154
67241510S69
1 151 8442456
148h919
47*'?
5695669777758928
10]
A .!C!
217
8296
819
4 !wK
e=,C 1056718749
0 0 0 t.! .!
16
Bf
808
21993976621 i
10414$84,8
6
.448648 -.
fA .
14817420"
~ 64
613
.,4
4864
BZ10:
124
148174202!«; !
+C!+ t.!+C>+1
!
+ !+ ';
+5~6+7+8+9
+1O+lf
+18+68
+]42qw! f4
*+44yc'4 c
+6 i t!+7ff+76 C!+778
»L 8
+6 p!+,c 7w
+ 94
+18+68
+142+2 h4+;%6
+442+545
+6 hb+711+7*0i778+758+69-
+57:+ '94
+1"+C»
+117+208+.,2*
+469+6>8~8~4
+1055+1 �h0~+1576+1876+ Of'+
+29 hf
~f17+208
~469+6 8
+8 �
+1 055gi30 h+157b+1876+ ZA1+»!L L
hP>
] ! !68
78.P,K
2011BO6
720478~bo877 75
104291:.54O1717
100h68
7S4
20132808
478*6OS47770
104C�f h4901709 h
710
1*. 4 !. 9
51. 7SO. 0
117.5168. 1Z »8.8
499. O685. 7982. 5
1496. 7
O.2 ~7 ~
16.4
51. 780. 0
117. 6168. �.
.S.*
497. f*8 .4976» 4
:484.7
At.ove &L
INPUT DATA".
LWL Ta TE15C> 16. 0 1 '. 1
VOLUME41446
r.'&.5
Cm C,~p.8 i
LOB/-1.48
P/D est.0. 65
D I A Htj10.0 7.0
t '+1
l 5 !S&pp�. C!
Csterr!+C!
At ldprops SAR est .:4.0 1 ~ *5.8
Vt t Wt Rf Rt? Rtr Ra Rtot a I EHF
tep?~ 4 k,I ?~ w4,
I
~ 21
0
21? }.1
.21
.21
.'1
.21
164' Hul I, 20/ Bul 0 .. 0' Atjove BL
INF'UT DATA".
LWL Ts Tf150 16.0 f 3. 1
LCB/� 1 ~ 'i4
P/D est.O. 65
VOLUME4 z?65
Cm C~p.91 .8'~i 8 ~ aJ
Htj At! K2+ f.0 81.8 1.50
DIAf C!.0
At Nprops E!AR est.=-.4. 0 1 . 65
Supp154.0
Cster rj+C!
Vkts Wt Rf Re Ra Rt ot s I EHPRtr
~ wDa
wCP ?a
c.C.
~ C?
~ A 4
C,A
1412 ~-
1.0:.0
04.05 ~ C!
6. 07.08.09.0
10. Cj1 i. 012. 01:". 0
14. 015. C!
1.0
? i. 04.05. 06. 07.08.09.0
10. 01 i. 0
2 0}14. 015. 0
67
510869
l.il5
18442456:148i919
4769I- 69c'
66977775S928
10154
71QC K
558
9171:iS.-
19462591
214 ] wK
506008706582029418
i0711
C!C!
0
16
80286794
2161-i9086107
102:.61816 .
000
00
16V 7I /
2927~
' 092
40185986
9916: '0
*1:
.i4
48*4
8210.
124148174
F i
2*4
*
486482
1021:4
148174202
26a
+ !+ '
+9
+18
+48+*6+85
+1 C�+124+14+1*1+178+195+211
+0+Cj+0+0+Cj+Cj+C!+C!+. C!
+0+Cj+Cj+1+1+1
+18~68
.I Fa
~44 ?
+545+6 i6+711+760+7?8+758+692+57 'i+ >94
+18+68
~142+~ 'ia+' i6
+442
+6=6+711+760+778+758
r
+ ''94
+l 'qC' ?
+117? C! 8
+ .6
+469+6 8+8@4
~ 1 0M%'
+l~~C! i+ 1576+187*+22C
+29 if
+14+54
+12.
+218~='40+490+666+870
+1101+1~60+1645+1958+? >98
~26*5+ i059
101i7C!
79 '
204 .
8
4865617S787 i
1 C 021 575171562 717i211 6
105
8161 91209S.928
:88249866 418007
1067-1 . 9 T
17 81i&&88
'i066C!
7 ~16. *«1. 4
52. *Bl . 4
119. 5170 ~ 8
41. 8'54.8
5!j! j
684.997*. 7
1479.4
02.47.5
17. 1i2 ~ 2
5g 9
S ~ .41 Zi5175m ~i245 ~ 9i6 ! ~ 5
514.969 .9958. 2
HL!I f !.!/ Ball b I 4 0 BL
I blPLJT DATA:LWL T~! T f150 16 0 1:..1
VOL Ulled. LCB'/� 1.
P/n e~t.!.! ~ 6 i
C!!!�9]
Cwp.818 ~ J
BAR est..b!
Hb Ab4.0 8]. B
I�2+ ]5 !
At Plprnps.=.4. 0 1
DIA1!! ~ 0
BBpp154 f!
Cistern+ 1
Wt Ff Rtr Ra Rtota] EHPP,b
O.c'. 4
7.517.1
"I I
00
7c?8 I
719«!"! j
.>94;
58769~
159 .1
54. 0C"
.*175 ~ =
45. 7:,59. 45l
P
!
C. jJ «
? *89. 8
]:i99. 0
]64' Hu] ], 20/ BL b, 5. 0'
I NPuT DATA:LWL Ta Tf VOLUME150 1*. C! 1~. ] 4=--265
LCB/� 1 ~:i4
P/D est.0. 65
Cm Cwp~ 91 .88.5
BAR eat..65
Hb Ab I 2+15.0 Bi. 8 1.50
G&pp154.0
Cistern+0
DIA10. 0
At Npr spa:4.0 1
RtrVolte Rtata] EHP
1.0~ !.!
4.05. 06.0F
8 ~ 0
10. 011. 012. 0
!,114. 015. 0
1.00
:i ~ 04.05.0*.07.0Q.O
10. 0]1.012. 01 'i.0
]4. 015. 0
? !e c.w"! ?
!a CJ
PM.I
I W
~ Cw
'? ?
7]«c' g
9171 871946IL o]
4]«L.
50 ii60087065B 0:94]8
10711
71QL L
8917
1 B71 9462591
41 5
6008706582029418
10711
0 0
0 0 01574
=Bi704
2c! 10
C T&Uf 4i~90;,
98
!
1-
486482
10:
4148]74
264
6]~
i44864
]0.�
i48174PO
264
+0+f !
f 0
+]
+6+ 7+8
+ 1!.!~]]
+]w
+0+]+4+8
+15+2 1+
+42+ C'
+64y7c
+86+97
+ii7
+]B+.6 E!
+142! w4
f:-.".6
+44 .yc 4L
+6 6+711+7*0q«!B
+7~8
+692pc 7g
+,94
+18+68
+142?4
+' 6+442yv4c
e*.,*+7]i+760+778+758+*9:
+ 'S'4
+14y c' 4
+-]8
+;40+490+666+870
+1101+1:-60
+]645+1958+2=98+2665+ ~059
+14+54
+122+"18+ 'F40+490+666+870
+1]01+1 60+1645+1958+2 .98+2665+ .~059
8 .'
8]712099
!9
ZBB449896 ~4]8000
106401=90717280
4:0:-71
105' 84.
8201400A 1 1
2950i9] .i
50 6
804106651 i9021724422028
014
0.'7 4
7.*17. ~� ~2 ~ 4
54. 484. 1
1.176. 4
«7. 0;br !
638. 4947. 0
1:-.SB. 5
164" Hul I . ».. 2'u}b, b. O' Abave
INF-UT DATA;,LWL Te Ef150 16. 0 I
K''B. 5
VOLUHE4 "r,*e.
LCD/-1. i4
F'/D est.0.6 i
Cm Cwp.91 .8
DI A Hb AbI i >. 0 *. 0 8]. 8
BAR est.*5
}:2i ] Cst em Npr opsI
Si3p p At"4. C>+0
V>'t s Wt Rf Rt ate I EHF'Rb
e,I I~ Cx,I
~ C. C.
>?r C.
]*4" Hul I . 20'/ Bulb, 7. i! Above BL
Ih}F'UT DATA."
LWL Te Tf150 16.0 I i. I
F'/D est.0. 65
VQLUHE4'265
Cm Cwp~ 9] .S~
LCB/� 1. 4-8 ~
DI A Hb Ab10.0 7.0 81. 8
BAR est.. 65
NpropsI
}:;2+ I
1. 50Csterr+0
Sapp154. 0
At.i4 �0
Vkts Wt Rf Rw Rtot el EHF'Rtr
e WM??
W C.�I
~ X.
~ C.! I tC
+
1 . i.!i.>
-.;�0
4.00
*. 07.08.09.0
10. 011. 012. 0
]4. 0]5. 0
1.0
~i�0
4.05.06.07
8.09.0
10. 011�.>
.01 .014. 015..>
71
Iu9
8?19462591
41 5c'0% ]
60087065S2029418
1071 I
71
~ C'
917138719462591
'~]I I41 i550 '16008706582029418
i.,!
0
1572
�4
68?1962
~768c'6}c
88]715~~4
0
0 0 0
70=.66
6681908I664
54598 >7}48I !i ~
6
I I&
486482
1!
124148]74Ig !Q
p
64
2 6
.44864
1 i1 4]48}74
+}+8
+54+9 I
+]46+20
+265
+=-94
+458+521q c'Bw
+6=9+694
+4
+101+216+ i72+5*0+771~994
+12 I+]447+1668+1880+. 08,
+18+68
+14.I
+, .6+44:+ I45+6 'ib
+711+760+778
~758~692pg 7W
+~94
+18+*8
+142+ ~4e., ib
+442
t-656
+7] 1+760+778+758+6%2
+ '.94
+14+54
P
+ 'IB
+ .40+490+*66+S70
+]101+I i60+1*45+195S~2298+2665+ 'i059
+14yR 4
+12+ 18+ F40
+490+666+.870
+] 101+I'60
+1645y I PlwB
+ 298+ -665+ 'i059
1 >6
8421446
19~'i.�
4085246*bc'
8 56I 100014245175912 I44=O.;47
1094]6918
160747048S
465159775. 79 I90
1215 I15499189 6
'7
'I 684
!
=.47.8
17. 8.7
56 ~ *87. 8
128. 91825*. 6i7]. 6
70960. 6
1~97. '9
2.6
8.5]9.7'i 7 ~ 9
*4. 'i
]00. 0146. 7208.:-
288. =.
410. 6571.756. 0
I 02 ! �41459.5
H.!l l. 20",:. E-.il b. 2. 0 Above
TINPOT DATA
Li!II Ta Tf1.C! lb. !
J.J
.B. 5} LE!/
i4R/D est
0. 65Cm Lep
.91 . 8'iVOLUME
K! 1 A1 0 ~ I. !
Hb Ab
=. 0 81.8
t; +1 Bapp1
BAR est.65
Cstei !i At Idprops:4.0 1
VIts Wt Ff Rt.' ot a! EHF'Rm Rapp
+040+0+0+! I
I~ A.
+0+ !
1 b4' Hu 1 1, i0/ Bul b, . 0' Above
I NF'UT DATA".
LNL Ta Tf
150 lb.O }~. 1LCB/
-0. BlVCIL.USE 8
4:784 B. 5Cm Cap
.91P/D est.
0 ~ *5
BAR est.. 65
I''; .+1 Bapp1. 50 154. 0
At Nprops:I4. 0 1
Cstern+0
D}A10. i.!
Hb Ab
2. 0 1:5.
Rtotal EHPRtrVI:ts Wt Rf
II mD~ AA
W?
e a.C
,I I
!
!
! !
6.!!7
8.09.0
11.01 !!
1~. 014. 015. 0
}.0"?
4.05. '0
6.07.0B.O9.0
1!! <!
-,, !} =,�r!
14�<!
15. 0
71~! C= I=! J
9} 71:.8!»1 '94*
2591! 1
41 5! ! / 1
6008706 >8, 029418
}07}i
74264558951
14 i820}7
685i44 ?
4 ?Be'
5 1462277'
850197*1
ii}O
Q!
1678
297
744-1=7
40856C! 87
1*501
0000
14686}
*.:818.6!�
5 i}9818}
1 97
6
48648?
102
I 4148174
64
*}3
486482
}02124148174! !
264
+0+I!
+ !+0+! !+0+0+0
+0+0+0+0+1+1+1,
+ '.
+4
+
+6
~}8+*8
+142+2 i4+',~6
+442+545+6 ib+7}1
+7*0tQ
+758+692yL
+ I94
+18+68
+}42
+ '.'.~
+442+545+6~6+7}1+7*0+778+758+692y c' 7
+ 94
+}4+54
++ 'lB+ 'i40
+490+666+S70
+l}01+1 i60+1645+1958+ 298~ I»*banc
+ I059
+14+56
+127+4P! IL
C'+ ~ITS+507~69}+90
+1}41+1409
+1705+2029+-%82~ -762+'171
1 :8BIE
!98
2927BSI I
4987*.' 46
8!.! } 91 �< �14! �0
174814,44
'>!,!9-'iO
108'94
841142161-017
40!.�C 1, 'I
65 !
S149
106951 891»100
28910
": ~ 4
7
17. 192 'I
8 .4c}a~. ~
}75. 4I4 6
'61. 7517. 4
697. 99*4. 9
14 4.8
0. ='..4
7.717. 6~X g ~ ~55 686. 0
1 6.17
50 2'' 6 1
5682. 79 5, I.!
1- 1.7
&L
INPUT DATA';LWL Ta Tf
i0 16I 0 1VQL LINE E~
4 I784 =,8. iCf!! Cwp
.8:LCB/
-t r. 81P/D est.
0.6 i
DIA10. 0
Hb t'2< 1 Bapp1 . 5.! 154 ~ 0
Csterrt«t!
At Npraps�'I4. !
BAR est. 65
Vl. ts RC P!I RL- Rtr Rtot. ~ I EHF-'
c.. Ue
!
~ LL!LL
A +r,! !! ~
P'?!'?
!??'? -64
164' HL!] I .:.0/. Bul b, 4. 0' BL
INPUT DATA."LNL Ta Tf.i50 1*. 0 1 ~. 1
LCB f.-0 ~ 81
VOLUPTE B4 i784 <8.
Cm Cap~ 91 .8
P/D est.0. 65
BAR est..65
BBpp154 ' 0
Cstern+A
At Npropsi4 ~ 0 1
DIA10. 0
! «2+11. 50
Hb4.0 «1
Rtatal EHPVkts Rtr
0 0 A164
::49
6091749i4 I9
507578::! 6 +2 i4
IIal
40
*.07.08.09 ~ 0
10. 01 l. 012. A15. 014. 015. 0
1.0
0~.04.05 ~6.07.08.09
lt!.0
1 l. 0l2. 0
i. 0
14. 0 -!
I 'P
~ L«i'? '?
LL~ L
2r LL
rr !~ L,II
~ LLLL
264
95114.:82017
2*85,44 ?
42855214
�
7«i2 «I850 l9761
1110 .
74264c'c'8
95114382017
685442
42855 -1462 -7
85019761
1 1 10,
t.!
1466
!L 6
624179~
?5
80021 >667
6
48648'
r
124148174'02
2 *1<
W4
486482
10.
124148174
!
264
+t!«1+ '«C
«BI
+1 1+15+19
7-,
+281
+ i/«4}«4L'
«0+2«8
+17+~0
+47+67+89
+11:+1 7+16.
+186+21.t!
+18+*8
«14 .+2 i4+ .;-6
+442«c 4c
+6 6+711+760+778
+758
q c'7w
+= 94
+18+68
+142«2 i4+', i6+44 .«c'4c
+6"'6
+711+76A
+778«758+692
+. 94
«14+56
+127
iiJC+ ' �
+691+902
+1141+1409+1 705+20 9«2082
+2762+ '-171
«14+56
+l"7? ICC W«i«rL'
+507+691«9r!
+1141+1409
+1705+20 -9
8+ a w 6 I?
+ 171
1 t.! 89 r-"
84214 ib
2i 66'it.! ? 4
4t�9
514465148156
1068C!1 i8421701621 712864~
10897
84814502i91~i063
4065521666028 ~ i4
107701 i91017L�=21 69I? 8 g
7.817. 6
7
8*. 212*. 4180. 0?50. 5
60. 8510. 1679.918. 8
1 i19.4
! ~
2.47 ~ 8
17. 8.6
56. 487. 4
B. 118 .5ICQ L
851=. 6681.918. 7
1:.1 .8
] &4' H .<i l .. '..'". S' lb. 5. C> Ab :ive E L
I f<PLJT DATA:LkL Ta TW] ..<0 16. >
F'/D est.C>.6 >
VOLL> ME4:i&4
LCB/� <! 8]
C » C. >p.91 .8..'«Bi ~
BAR e t.. 65
I::"e 11 ~<"!
Lsterr<Be p p] ..<4. <. !
DTA10.0
Npl opeAt«4 <.!+ !
Rtot n] EHPRepp Ra <I:te Wt
< ! ~! C
~ C wCC«t !
. C.
.«79. 9C' !~ «1 .:.
702. 4941. 4
4. 1
164' HL l l,:.<!/ Bul b, 6. O' Above
]NPLJT DATA:LWL Ta Tf150 16. 0
F'/D est.0
VOLUf1E 84:«784 «8.5
Cm C>!>p.91 .B:.«
LCB/-O. 81
ei Sapp1. <0 ]54. 0
DI A Hb Ab10.0 6.0 1 «5.3
NpropsAt'«4, C>
E AR est .. 65
C,stern+ .>
Vl:ts Wt R$ Rapp Rb Rtot el EHF'
e14+56
+127!wce~~de'a+
« 'F~ a~«
CcCC
0 0 C! 6
w4
4864Ci !?ldI
,I « 10
]48174
4, .><'!
6.0
8.09. C>
1O�C>
]].0 !
] «,0
14. 015. 0
1. C>C!
.«. C!
4.05 ~ 0
7.0B.O9.0
10. 0] f.<.>1 ..01:-. O
14.0<!
74264~~B
95l]4 .8
=0]7268 <.«44 ?
,I 8 ~C' «
85019761
11102
7464
! ~B
95114 «S
7,tbe&
:4424285c' >]4
6 .27
850]
'] 1';:
1:"
L CtM r170l
49 *!c'9 ?
0 02
12
*].c'
�
1 *48
47'««7 !! v ' 6w»; >
44864
]C! .1 �
l48174?<! «C
-64
ei+I]
e76+ 1-.'.!e='OB+"94
+�,87e48~e >8*
+68*78'
+88=e97 >
el<0* >
e~+ '.8
ei 18eg< c'
+446+681+949
el :7e 1 E'
+18=8+ 1 «7e. 4:8
708iI
+18+68
e, ]I
+44 >
e.A <+6~6+7]1+76C>
+778+7 >8+69 .ec tW!+. 94
+iSe6S
e]42e !w4
+ e442ev4<
eb .6
+, i]+760+778e758eb9 >eg7 «e, «94
e ]4+ >6
+1 7e! ' Je i'g !
e~ �
e691+9 !
+1 ]41
+1409e]705+!n
+ .«82e ! !
+ «171
e507+691+90.
+li41+1409+1705+e «8~>
i 76 !
+ ~ ]7]
]0940-
87] 509
6
dJ]<*9678686
]]246]44]5
7w 9K'
21 896="896=
il4
9591688~ 607
:«6974946*:«*1BOil99
1 6441595 «19 -6.!
«*6 1
8.118. 5
59. 4
1:- >.4
19=.6266. 7
0..«
2.78.8
- .! ~ 74C! 0
*B. 1106.:1 56.:«
,I$ 4
4 7.1587. 9769 .:.'
] C>17,] < ' 4
Re/aged ggg /gal grant Regoggg
PagesAuthor and Title PriceHITSG No
Goudey, C. A., S. P Loutr el, and A. 8, Clif ton.
An Improved Tr asl Door Hook-up System.
79-22 free
83-11 Goudey, C. A. and R. S. Hant. Full Scale
Resistance Tests of Yankee Trasls of' both
Nylon and Polyethylene Construction.
12 f'ree
Goudey, C. A. and H. H. Linskey. Retrofit Sail-
Assist on Nes England Fishing Vessels.f'r ee83-1 2
83-32 free
84-10 Goudey, C. A. and C. A. Holberger. The Development 4of Fishing Trawl Testing Capabilities at NSRDC,
f'r ee
84-1 5 Nilson, David Gordon and T. P. Rorakianitis.
Potential f' or Advanced Br ayton-Cycle Enginesf or Commerci al F i shi ng Vessel s.
f ree
109 94. 50Rilson, David Gordon and T. P. Korakianitis.
High-Ef ficiency Br ayton-Cycle Engines f' orHari ne Propulsion.
85-10
Heliotis A. D. and C. A. Goudey. Tos Tank Results 40of Bulbous Boa Retrofits on New England TrawlerHulls.
85-7 t ree
85-1 3 Goudey, C. A. and A. D. Heliotis. The Ef feet of 47Bulbous Boa Retrofits on the Resistance and
Seakeeping of a 50 Heter Freshf'ish Stern Tr aaler.
free
85-33 Goudey, C, A. Test Results f'rom the New England 10Trawl Net Training Courses. Reprinted from theCommer'cial Fisheries Ness.
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These reports can be ordered from;
HIT Sea Gr ant ProgramCenter for Fisheries Engineering Resear'ch
Bldg. E38-37b, 292 Hain StreetCambridge, HA 02139
Goudey, C, A., ed. and L. Pukshansky, translator. 7Russian Translations: On Trasl Hydrodynamics byH. A. Nisurkin and V, H Rostyukov; HrdrodynamicHater Channel for Fishing Gear Research by V, A. Belov.