2005Safety at Sea Seminar
Slide 1
Student Projects For the New Student Projects For the New Navy 44 Sail Training CraftNavy 44 Sail Training Craft
Assoc. Prof. Paul Miller, D.Eng., PEAssoc. Prof. Paul Miller, D.Eng., PE
Naval Architecture and Ocean Engineering DepartmentNaval Architecture and Ocean Engineering DepartmentUnited States Naval AcademyUnited States Naval Academy
2005Safety at Sea Seminar
Slide 2
Vessel BackgroundVessel Background
• 44-Foot Offshore 44-Foot Offshore Sailing Craft for USNASailing Craft for USNA– 1939 Luders Wood Yawl1939 Luders Wood Yawl– 1966 Luders Glass Yawl1966 Luders Glass Yawl– 1985 McCurdy and 1985 McCurdy and
Rhodes SloopRhodes Sloop– 2003 PYD sloop2003 PYD sloop
Safety is Paramount – Low Maintenance –10 Crew – Good RatingSafety is Paramount – Low Maintenance –10 Crew – Good Rating
2005Safety at Sea Seminar
Slide 3
Student Research Opportunities Student Research Opportunities at USNAat USNA
• Summer InternshipSummer Internship– ~120 manhours~120 manhours
• Independent Independent Research ProjectResearch Project– ~ 140 manhours~ 140 manhours
• Capstone CourseCapstone Course– ~ 190 manhours~ 190 manhours
• Trident ProjectTrident Project– ~ 580 manhours~ 580 manhours
Total student involvement Total student involvement was about 2000 manhours!was about 2000 manhours!
2005Safety at Sea Seminar
Slide 4
Presentation OverviewPresentation Overview
• Nine student projects by eleven Nine student projects by eleven students ranging from materials to students ranging from materials to Computational Fluid Dynamics.Computational Fluid Dynamics.
• Student projects both educational Student projects both educational and useful in Navy 44 design and useful in Navy 44 design developmentdevelopment
2005Safety at Sea Seminar
Slide 5
Incline Experiment, Full-Scale Incline Experiment, Full-Scale Resistance and VPPResistance and VPP
• Researcher: Aaron Researcher: Aaron DeMeyerDeMeyer
• Goals: Establish Goals: Establish baseline stability baseline stability and resistance data and resistance data and develop a VPP and develop a VPP tool for future tool for future research.research.
2005Safety at Sea Seminar
Slide 6
Full-Scale InclineFull-Scale Incline
• Incline experiment Incline experiment at full-load (vs IMS) at full-load (vs IMS) CSNTS conditionCSNTS condition– More stores, More stores,
equipment, sparesequipment, spares
• Two digital Two digital inclinometersinclinometers
• 8500 pounds8500 pounds• Righting moment Righting moment
decreased 1.2%decreased 1.2%
Incline Experiment for Navy 44Regression
y = 1687.7x
-2000
0
2000
4000
6000
8000
10000
12000
14000
16000
-1 0 1 2 3 4 5 6 7 8 9
Degrees of heel
Rig
hti
ng
Mo
me
nt
(ft-
lb)
Uncorrected (for added weight) Righting Moment
2005Safety at Sea Seminar
Slide 7
Full-Scale ResistanceFull-Scale Resistance
Resistance Curves (Raw Data)
0
100
200
300
400
500
600
3.0 4.0 5.0 6.0 7.0 8.0
Boat Speed (knots)
Re
sis
tan
ce
(lb
)
Prop Aligned VPP Estimate
VPP (updated) Trend (prop aligned)
VPP provided by Chris Todter- Initial used parametric drag prediction- Updated included strut, shaft, prop, paint and biofouling factors
2005Safety at Sea Seminar
Slide 8
Capstone Design ProjectCapstone Design Project• Researchers: Mark Researchers: Mark
Arvidson, Peter Arvidson, Peter Firenze, Cecily Firenze, Cecily TaylorTaylor
• Goal: Develop a Goal: Develop a preliminary design preliminary design of a new Navy 44 of a new Navy 44 using the same using the same constraints as the constraints as the current vesselcurrent vessel
X-452
Frers 41
J44
C&C 39
J46 Defiance 44
Sweden 390
Swan 44 Mk II
Navy 44
Baltic 40
Hallberg-Rassy 46
30
35
40
45
50
55
120 140 160 180 200 220 240 260 280 300 320
D/L
LO
A (
ft)
1982-1990 1990-Present
Navy 44Defiance 44
Swan 44 Mk II
Sweden 390
Hallberg-Rassy 46
Baltic 40
J46
30
35
40
45
50
55
10 12 14 16 18 20 22 24
SA/D ratio
LO
A (
ft)
1982-1990 1990-Present
2005Safety at Sea Seminar
Slide 9
Capstone Design ProjectCapstone Design Project• All design aspects evaluated and All design aspects evaluated and
discussed with outside designersdiscussed with outside designers• VPP used to improve VPP used to improve
performance incrementallyperformance incrementallyM&R "Mk 2" Mid 44
preliminary
LOA (ft) 43.9 44.0 44.0LWL (ft) 34.2 36.8 38.4Beam (ft) 12.4 12.4 12.4Draft (ft) 7.25 7.42 7.42Disp (lb) 28,600 27,700 24,200Sail Area (sq ft) 1017 1080 1017Disp-Length ratio 320.3 249.1 190.8SA-Disp ratio 17.4 18.8 19.4LPS (deg) 129 130 143
2005Safety at Sea Seminar
Slide 10
Capstone Design CourseCapstone Design Course
2005Safety at Sea Seminar
Slide 11
Capstone Design ProjectCapstone Design Project
0
250
500
750
1000
1250
3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5
Speed (knots)
Res
ista
nce
(lb
)
M&R44 up MID44 up M&R44 dn MID44 dn Luders dn
All the designs had roughly the same drag at 6.5 knots boat speed upright. (S/L ratio of 1.1)The biggest differences were seen at higher speeds (winds greater than 10 knots).
2005Safety at Sea Seminar
Slide 12
Laminate UpgradeLaminate Upgrade
• Researcher: Mark ArvidsonResearcher: Mark Arvidson
• Goals: Determine the hull laminate with Goals: Determine the hull laminate with the best combination of toughness, cost, the best combination of toughness, cost, stiffness and strength to ABS Guidestiffness and strength to ABS Guide
• Approach:Approach:– Laminate analysis programsLaminate analysis programs– Coupon and panel testsCoupon and panel tests– Impact testsImpact tests
2005Safety at Sea Seminar
Slide 13
Laminate SelectionLaminate Selection
0
50
100
150
200
250
300
350
0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00
Position (in)
Lo
ad
(lb
s)
Vinyl Ester
4200 Epoxy
0
0.5
1
1.5
2
2.5
3
3.5
C0 C1 C2 C3 C4 L1 L2 L3 L4 R1 R2 R3 R4 R5 R7 Test Laminates
No
rmal
ized
Yie
ld/W
eig
ht
Rat
ios
2005Safety at Sea Seminar
Slide 14
Laminate SelectionLaminate Selection
2005Safety at Sea Seminar
Slide 15
On Water TestingOn Water Testing
2005Safety at Sea Seminar
Slide 16
Alternate Wood LaminateAlternate Wood Laminate
• Researcher: Kent SimodynesResearcher: Kent Simodynes
• Goals: Using ABS, Navy and other Goals: Using ABS, Navy and other analysis methods determine an analysis methods determine an alternate wood laminate for the Navy 44alternate wood laminate for the Navy 44
• Approach: Analysis, coupon and panel Approach: Analysis, coupon and panel teststests
2005Safety at Sea Seminar
Slide 17
Alternate Wood LaminateAlternate Wood Laminate• All three methods All three methods
agreed with test agreed with test results for Carvel results for Carvel plankingplanking
• Cold-molded Cold-molded were 160-205% were 160-205% stronger than stronger than ABS and Navy, ABS and Navy, 77-120% for 77-120% for CLT/Tsai-WuCLT/Tsai-Wu
Specific Flex Strength vs. Material
We
t M
ah
og D
ry M
ah
og
C-M
ah
og
O-G
lass
C-M
ah
og
O-E
po
xy
C-W
RC
O-M
ah
og
(G
)
C-W
RC
O-O
ak
(G)
C-W
RC
O-G
lass
C-W
RC
O-O
ak
C-B
als
a O
-Ma
ho
g
C-B
als
a O
-At.
Ce
da
r
C-D
ou
g F
ir O
-Gla
ss
0
5000
10000
15000
20000
25000
30000
Material Type
Sp
eci
fic
Fle
x S
tre
ng
th (
psi
)
25237
11305
23697
20279 20287
25960
21611
17580
11837
26550
28550268550
Using the same FOS, wood would be about 400 pounds (2%) heavier...
2005Safety at Sea Seminar
Slide 18
Keel Section and ShapeKeel Section and Shape• Researcher: Aaron DeMeyerResearcher: Aaron DeMeyer• Goals: Improve the performance of the new Goals: Improve the performance of the new
boat through keel planform, section and VCG boat through keel planform, section and VCG placement and structural modifications.placement and structural modifications.
• Approach: VPP, tank testing, CFD (with help Approach: VPP, tank testing, CFD (with help from Paul Bogataj)from Paul Bogataj)
• Solution: J5013 with 5% area reduction and Solution: J5013 with 5% area reduction and 6” lower VCG yielded an average 8% lower 6” lower VCG yielded an average 8% lower keel drag for an Olympic course at 6, 12, 20 keel drag for an Olympic course at 6, 12, 20 knots wind speed. 0-8 sec/mi improvement. knots wind speed. 0-8 sec/mi improvement.
2005Safety at Sea Seminar
Slide 19
Grounding ComparisonGrounding Comparison
• Researcher: Adam DriessenResearcher: Adam Driessen
• Goals: Determine if IMS-style bulb Goals: Determine if IMS-style bulb influences grounding (and influences grounding (and ungrounding) characteristicsungrounding) characteristics
• Approach: Gravity towed tank testing in Approach: Gravity towed tank testing in Coastal Lab 2-D beach tankCoastal Lab 2-D beach tank
2005Safety at Sea Seminar
Slide 20
Grounding ComparisonGrounding Comparison
Set up – 2 Hull/Keel Models; Constant Force, Not Constant Speed
2005Safety at Sea Seminar
Slide 21
Grounding ComparisonGrounding Comparison
2005Safety at Sea Seminar
Slide 22
Grounding ComparisonGrounding Comparison
Velocity Avg Force COV(kts) (lbs)
MR44 6.88 1.87 8.6%MID44 7.43 2.01 8.2%MR44 3.33 0.92 19.1%MID44 3.4 0.56 18.0%
Slope = 1:8
Velocity Avg Force COV(kts) (lbs)
MR44 6.88 2.14 8.9%MID44 7.43 2.14 16.1%MR44 3.33 0.95 15.5%MID44 3.4 0.91 21.5%
Slope = 1:12
Pull off force less for bulb twice, once for fin, once was equal.
2005Safety at Sea Seminar
Slide 23
Rudder Design ComparisonRudder Design Comparison
• Researcher: Ted HuebnerResearcher: Ted Huebner
• Goals: Determine relative performance Goals: Determine relative performance in a sail training environment of spade in a sail training environment of spade and skeg rudders.and skeg rudders.
• Approach: Full scale and tank testing Approach: Full scale and tank testing (resistance and tactical diameter)(resistance and tactical diameter)
2005Safety at Sea Seminar
Slide 24
Rudder Design ComaparisonRudder Design Comaparison
Condition RadiusBoat Lengths
Full scale 1.63
Old Hull Existing Rudder 1.39Old Hull Elliptical Spade 1.24
Old Hull Big Spade 1.22Old Hull Elliptical Skeg 1.22
New Hull Existing Rudder 1.89New Hull Elliptical Spade 1.35
New Hull Big Spade 1.22New Hull Elliptical Skeg 1.22
2005Safety at Sea Seminar
Slide 25
Rudder Design ComparisonRudder Design Comparison
2005Safety at Sea Seminar
Slide 26
Rudder Design ComparisonRudder Design Comparison
0
0.005
0.01
0.015
0.02
0.025
0.03
0.035
0.04
0.045
0 0.05 0.1 0.15 0.2 0.25 0.3Cl
Cd
trap skeg ellip spade trap spade ellip skeg
Poly. (ellip skeg) Poly. (trap spade) Poly. (ellip spade) Poly. (trap skeg)
2005Safety at Sea Seminar
Slide 27
Tank Test/CFD/VPP StudyTank Test/CFD/VPP Study
• Researcher: Jon SilverbergResearcher: Jon Silverberg• Goals: Compare modern prediction Goals: Compare modern prediction
methods and improve preliminary methods and improve preliminary designdesign
• Approach: CFD, tank testing and VPPApproach: CFD, tank testing and VPP
2005Safety at Sea Seminar
Slide 28
Tank TestingTank Testing
• New model built to PYD New model built to PYD preliminary designpreliminary design
• Data RecordedData Recorded– DragDrag– LiftLift– Yaw MomentYaw Moment– PitchPitch
• Tests includedTests included– Upright ConditionsUpright Conditions– Sailing ConditionsSailing Conditions– Viscous CorrectionsViscous Corrections
• Performed more than Performed more than 570 runs570 runs
2005Safety at Sea Seminar
Slide 29
SPLASH – CFDSPLASH – CFDSPLASH – CFDSPLASH – CFD
• Calculated inviscid fluid velocities across a discretized hull for all tank test cases
• Calculated inviscid fluid velocities across a discretized hull for all tank test cases
Code by Bruce Rosen of South Bay Simulations and Joe Laiosa from Navair at Patuxent River
Code by Bruce Rosen of South Bay Simulations and Joe Laiosa from Navair at Patuxent River
2005Safety at Sea Seminar
Slide 30
PCSail VPP modified for tank PCSail VPP modified for tank and CFD Resultsand CFD Results
2005Safety at Sea Seminar
Slide 31
Performance PredictionsPerformance PredictionsLow wind speeds showed variable results due to simplifications in the aerodynamic model
Low wind speeds showed variable results due to simplifications in the aerodynamic model
All other wind speeds showed excellent correlation between all velocity predictions
All other wind speeds showed excellent correlation between all velocity predictions
2005Safety at Sea Seminar
Slide 32
Final VPP ResultsFinal VPP Results
• Used Tank results and Used Tank results and CFD iterationsCFD iterations
• VPP and CFD used to VPP and CFD used to look at variations of rig, look at variations of rig, weight, stability, rudder weight, stability, rudder designdesign
• Suggested changes Suggested changes documented and documented and discusseddiscussed
2005Safety at Sea Seminar
Slide 33
Final Results?Final Results?• Info from student projects documented Info from student projects documented
and used to develop “consensus” and used to develop “consensus” design traits.design traits.
• New hull, keel, and rudder shapes.New hull, keel, and rudder shapes.
• New cockpit layout.New cockpit layout.
• New structural design.New structural design.
• Students are now submariners, pilots, Students are now submariners, pilots, SWOs and MarinesSWOs and Marines
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