Hydrodynamic Characterisation and Structural Design Analyses of an Airboat

Ibelema Faango Keribo^1, and Daniel Tamunodukobipi^{2, 3}

¹Department of Marine Engineering, Rivers State University, Port Harcourt, Nigeria

²Department of Marine/ Mechanical Engineering, Niger Delta University, Wilberforce Island, Bayelsa State, Nigeria

³Department of Marine Engineering, Rivers State University, Port Harcourt, Nigeria;Energy Mechanics Resource Center, Korea Institute of Science and Technology, Seoul, Korea

Cite this paper:
Ibelema Faango Keribo and Daniel Tamunodukobipi. Hydrodynamic Characterisation and Structural Design Analyses of an Airboat. American Journal of Mechanical Engineering. 2017; 5(5):199-204. doi: 10.12691/ajme-5-5-2

Abstract

This paper presents the structural design and hydromechanics performance characterization of a prototype airboat of length= 2.42m, beam= 1.11m, draught= 0.32m, and powering =30 kW. Modified Savitsky’s model and test-data are utilized for the analysis. The results show that the hull-trim increases from static trim to a peak value of 5.2° at Fn =2.50 in the non-planing speed regime; and then decreases to a plateau in the planing-speed regime. This phenomenon is explained by the aftward drift of the point of action of the resultant lift force towards the centre of gravity. For higher Froude number, bottom-velocity ratio increases towards unity: i.e. a reduced wake effect. Resistance curve for airboat is “Ogive” shape, rather than parabolic; whereas the effective power is parabolic. Correlation of analysis and test data shows a good agreement, except at transition speed. Therefore, the analysis is valid for characterizing airboats parameters.

Keywords:
hydrodynamic design of airboat stability analysis of planing hull resistance and speed characteristics design and structural analysis of airboat

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