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The Impact Analysis for Water-Entry of Cylindrical Body  

독고욱 (정회원·국방과학연구소)
김인학 (국방과학연구소)
Publication Information
Journal of the Computational Structural Engineering Institute of Korea / v.15, no.1, 2002 , pp. 1-8 More about this Journal
Abstract
When a body enters waters, its original kinetic energy or momentum is distributed among the body and surrounding water in the form of added mass. Due to the transfer of the energy or momentum, the bode is subjected to the hydrodynamic impact forces and acceleration. This impact behavior can be an important criterion of submersible vehicle launched to the air. In this paper, based on Life-boat model, an approximate method is proposed for the evaluation of the forces and responses of cylindrical rigid bode by water entry impact. The impact forces are calculated by yon Karman's momentum theory and motion responses the body, especially acceleration, are calculated by a numerical integration of the motion equations derived by hydrodynamic force equilibrium. The proposed method is expected to be a simple but efficient tool lot the preliminary design or motion analysis of a body subjected to water entry impact.
Keywords
Water entry; Momentum force; Impact force; Life-boat model;
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