# Second Order Effect Induced by a Forced Heaving

• Kim, Won-Joong (Department of Naval Architecture and Ocean Engineering, Pusan National University) ;
• Kwon, Sun-Hong (Department of Naval Architecture and Ocean Engineering, Pusan National University)
• Accepted : 2016.02.05
• Published : 2016.03.31

#### Abstract

In this paper, the $2^{nd}$ order hydrodynamic force effect of heaving submerged circular cylinder is considered, with the linear potential theory. Boundary value problem (BVP) is expanded up to the $2^{nd}$ order by using of the perturbation method and the $2^{nd}$ order velocity potential is calculated by means of integral equation technique using the classical Green's function expressed in cylindrical coordinates. The method of solving BVP is based on eigenfunction expansions. With different cylinder heights and heaving frequencies, graphical results are presented. As a result of the study, the cause of oscillatory force pattern is analyzed with the occurrence of negative added mass when a top of the cylinder gets closer to the free surface.

#### Acknowledgement

Grant : BK21플러스

Supported by : 부산대학교

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