### “Slow Drift-Oscillations of a Ship in Irregular Waves”

**Authors:**Odd M. Faltinsen and Arne E. Løken,

**Affiliation:**NTNU and Det Norske Veritas (DNV)

**Reference:**1980, Vol 1, No 4, pp. 195-213.

**Keywords:**Hydrodynamics, slowly varying wave forces, wave drift forces, strip theory, mooring, potential theory

**Abstract:**A procedure to calculate horizontal slow drift excitation forces on an infinitely long horizontal cylinder in irregular beam sea waves is presented. The hydrodynamic boundary-value problem is solved correctly to second order in wave amplitude. Results in the form of second order transfer functions are presented for different, two-dimensional shapes. It is concluded that Newman´s approximative method is a practical way to calculate slow drift excitation forces on a ship in beam sea and it is suggested that it may be used in a more general case. Applications of the results for moored ships are discussed.

PDF (4646 Kb) DOI: 10.4173/mic.1980.4.1

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**BibTeX:**

@article{MIC-1980-4-1,

title={{Slow Drift-Oscillations of a Ship in Irregular Waves}},

author={Faltinsen, Odd M. and Løken, Arne E.},

journal={Modeling, Identification and Control},

volume={1},

number={4},

pages={195--213},

year={1980},

doi={10.4173/mic.1980.4.1},

publisher={Norwegian Society of Automatic Control}

};