Applied Mathematics and Mechanics

, Volume 20, Issue 10, pp 1150–1159

# Water surface wave radiation generated by multiple cylinders oscillating with identical frequency

• He Wuzhou
Article

## Abstract

The water surface wave radiation problem caused by multiple cylinders oscillating with identical frequency was solved in frequency domain by the boundary element method using simple Green' s function in the inner water region combined with the eigenfunction expansions in the outer water region. The numerical method is suitable to the situation of constant depth of outer regions and complicated boundary conditions of inner region, while the oscillating modes, motion amplitudes and phases of the cylinders may be different from one another. The second order potential and hydrodynamic forces acting on each cylinder were evaluated completely by perturbation method. Compared with the case of single oscillating cylinder, hydrodynamic interference phenomena, such as weve resonance and negative added mass, of the radiation problem due to the oscillatory motions of multiple cylinders are identified which is of engineering importance to the design of moorings and other facilities involving multiple structures.

## Key words

plane water surface wave radiation problem solution in frequency domain second order hydrodynamic force added mass damping coefficient

O353.2

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