The Most Efficient Boat Hull at Varying Water Speeds

The Most Efficient Boat Hull at Varying Water SpeedsLauren CasulliQuestion Which boat hull is the most efficient at different water speeds?

PurposeThe purpose of this experiment was to determine the most efficient boat hull.

Background InformationThere are six main hull shapes in use today:Flat BottomCatamaranV BottomTri HullPontoonBargeHypothesisThe most efficient boat hull at any speed is the tri-hull because the air tunnels reduce drag.

MaterialsWoodWater pumpDual Force SensorWooden troughBand saw, table saw, drill, sanderEye hooks (4)StringCopper pipeTygon tubingBall valvePipe clampsProcedureDraw outlines of top view and side view of boat Cut woodSand and finalize shapeAttach force sensor to one end of troughAttach eye hooks to bow of boat, connect string from boat to sensorFill trough with water, controlling the speed of water with ball valveAllow water speed to reach 0.0318 m/sec, place first boat in trough and record sensor reading for ten seconds. Repeat two more times.Repeat with other three boats, do not change water speedChange the water speed to 0.0477 m/sec and measure the force on all four boats with sensorRepeat at 0.0636 m/sec

Photographs Pump Configuration

Trough Set Up

Hull Bottoms

Boat Hull TopsBoat Hull TopsVariablesIndependent VariablesWater speedHull shape

Dependent VariablesForce on hulls

ControlRaftConstantsPump WaterTroughSensorWater speeds

GraphsThe Average Drag of Different Hull Types at a High SpeedThe Average Drag of Different Hull Types at a Medium SpeedThe Average Drag of Different Hull Types at a Low SpeedHighRaftBargeV BottomTri HullTrial 10.36980.1780.10050.08993Trial20.27850.18220.10180.08416Trial 30.40340.19220.10710.07907Averages0.35060.18410.10310.08440T-TestsRB0.04263 BVB0.0007465 VBTH0.06600RVB0.001349 BTH0.005291RTH0.01992Data High Speed Medium SpeedMediumRaftBargeV BottomTri HullTrial 10.21640.049670.031680.01497Trial 20.21770.038220.031710.02297Trial 30.20960.044390.030650.02388Averages0.21460.044090.031350.02061TTESTRB0.0007037 BVB0.06268 VBTH0.07156RVB0.0001398 BTH0.05607RTH0.0005502Slow SpeedSlowRaftBargeV BottomTri HullTrial 10.1580.020.022160.0005921Trial 20.15230.030060.023370.003039Trial 30.13750.029630.022230.001069Averages0.14930.026560.022590.001567T-TestsRB0.03970 BVB0.3252 VBTH0.0002997RVB0.03557 BTH0.01257RTH0.02857ConclusionThe hypothesis was supported as the Tri-Hull consistently had the least amount of resistance at any speed of water.

The V-bottom was a close second as the best hull as it had significantly less resistance than the flat bottom and raft. There is almost no significant difference between the V bottom and Tri-Hull.

Significance of ExperimentThis experiment was significant because it contributed to the idea that not every hull is suitable for every activity. The experiment demonstrated that certain hulls would be more efficient and effective for activities at lower water speeds while some hulls were better for high speed activities.Work CitedZidock Jr, A. (1999, July/August). Boat Hull Design. Retrieved September/October, 2010,

from Commonwealth of Pennsylvania Fish and Boat Commissionwebsite: http://

www.fish.state.pa.us/anglerboater/1999/julaug99/boathull.htm