the effect of micro bubbles and bulbous bow on the aerodynamic efficiency of a boat
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The Effect of Micro Bubbles and Bulbous Bow on the Aerodynamic Efficiency of a Boat. Harry Kucharczyk. Need. $438 Million spent on annual boating fuel (Lipton 95) 99.8% of goods are transported by ships Carbon Dioxide emissions continue to rise. www.unido-ichet.org. Knowledge Base. - PowerPoint PPT PresentationTRANSCRIPT
The Effect of Micro Bubbles and Bulbous Bow on the Aerodynamic
Efficiency of a BoatHarry Kucharczyk
Need$438 Million
spent on annual boating fuel (Lipton 95)
99.8% of goods are transported by ships
Carbon Dioxide emissions continue to rise
www.unido-ichet.org
Knowledge BaseBulbous Bow o Reduces shock wave
oDecrease in friction drag
http://www.globalsecurity.org
www.marinefirefighting.com
Knowledge BaseMicro Bubbles
•Inserted in the boundary layer
•Decreased viscosity and density of the fluid
www.impactlab.com
Literature ReviewMcCormick and Bhattchara (73)- injected
hydrogen micro bubbles into the turbulent boundary layer
Madavan (84)- location and distribution of bubbles are essential
Kato (94)- determined reduced skin friction drag by 80% through the use of micro bubbles
Kodama (00)- performed experiments in a water tunnel with microbubbles generated in an air injection chamber by injecting air through a porous plate
Engineering GoalsExamine the effects of passive and active flow
in boat drag reduction
PurposeReduce skin friction drag by using methods
of passive and active flow control
Boat with Bulbous Bow n=2
Measure mass and acceleration to calculate the force
Analyze data using SPSS One Way ANOVA and a Scheffe post Hoc test.
Insert Microbubbles in the Boundary Layer using a porous plate (200-400 micrometers)
Normal Boat n=2
Experimental Setup
Porous Plate
Bulbous Bow
Newton’s Second Law
Force = Acceleration X Mass
Force = Mass X (Velocity1 – Velocity2) (Time1 – Time2)
Do AbilityWater Tunnel is accessible in the lab Boat has already been constructedBulbous bow can easily be inserted into the
boatMicrobubbles can be made through simple
appliances
BudgetItem Vendor Category # Size QuantityPrice
Water Tunnel Lab
Boat Lab
Porous Plates
ICT Internationa
l0604D04-
B15M15in
radius 5
Micro Acquarium Bubbler Rena 17163057048 2in 1 $4.44
Air Injector Lab
Bibliography Culley, Dennis. "Active Flow Control Laboratory." NASA - Active Flow Control. NASA. 29 Feb. 2008
<http://www.grc.nasa.gov/cdtb/facilities/flowcontrollab.html>. Donovan, John, and Linda Kral. "Active Flow Control Applied to an Airfoil." American Institute of Aeronautics
(1998). Kato, H., Miyanaga, M., Haramoto, Y. & Guin, M. M. 1994 Frictional drag reduction by injecting bubbly water
into turbulent boundary layer. Proc. 1994 Cavitation and Gas-Liquid Flow in Fluid Machinery and Devices ASME 190, 185-194.
Kodama, Y., Kakugawa, A., Takahashi, T., and Kawashina, H., 1999, “Experimental Study on Microbubbles and Their Applicability to Ships for Skin Friction Reduction”, 1st Int. Symp. on Turbulent Shear Flow Phenomena, Santa Barbara, U.S.A., pp.1-6.
Liou, William W. Microfluid mechanics. New York: McGraw-Hill, 2005. Lipton, Douglas W., and Scott Miller. "Recreational Boating in Maryland: An Economic Impact Study, 1993-
1994." 6 Mar. 1995. Maryland Marine Trades Conference. Madavan, N.K., Deutsch, S., Merkle C.L., 1984, “Reduction of Turbulent Skin Friction in Microbuubbles”,
Phys. Fluids, Vol. 27, pp.356-363. McCormick, M.E., Bhattacharyya, R., 1973, “Drag Reduction of a Submersible Hull by Electrolysis”, Naval
Engineers Journal, Vol.85, No.2, pp. 11-16. Pike, John. "Bulbous Bow." Global Security. 7 Oct. 2006. <http://www.globalsecurity.org>. Scott, Jeff. "Vortex Generators." Aerospaceweb.org | Reference for Aviation, Space, Design, and Engineering.
14 Jan. 2001. <http://www.aerospaceweb.org/question/aerodynamics/q0009.shtml>. Washington University in St. Louis (2009, March 18). Engineer Devises Ways To Improve Gas Mileage.
ScienceDaily Yoshida, Y., Takahashi, Y., Kato, H., et al. 1998A, “Study on the Mechanism of Resistance Reduction by Means
of Micro-Bubble Sheet and on Applicability of the Method to Full-Scale Ship“, 22nd ONR Symp. on Ship Hydrodynamics, pp.1-16.