Til hovedinnhold

Wave drift forces and responses in current

Wave drift forces and responses in current

Kategori
Vitenskapelig Kapittel/Artikkel/Konferanseartikkel
Sammendrag
The influence from a current on wave drift forces and resulting slowly varying vessel responses can be quite significant. In this paper the effect is reviewed and further investigated. Several works have been published on this complex topic during the last 20–25 years, while it is only to a little extent taken consistently into account in standard industry tools. Simplified methods are often used, if any, and /or empirical correction from model test data. Thus there is a need to improve standard tools in this respect.

The effects on slowly varying vessel motions and resulting extreme mooring line loads are demonstrated through time series sequences from selected, previous model tests with FPSO’s and semisubmersibles in steep irregular waves. Wave-current interaction effects that can be larger than the effects from current and wind alone are identified. It is also confirmed from these examples that extreme mooring forces usually occur due to extreme slow-drift motions.

An overview description is given of a new, general numerical potential theory code for industry use, MULDIF-2, where wave-current-structure interaction is consistently included as a basic element in the formulation. Main items in the approach are addressed and referred to previous works in the literature. Results from an initial comparison against previous results on drift forces on a vertical column are given, and a good agreement is found. Further verification and validation work is in progress.
Språk
Engelsk
Forfatter(e)
  • Carl Trygve Stansberg
  • Elin Marita Hermundstad
  • Jan Roger Hoff
  • Rolf Jarle Baarholm
Institusjon(er)
  • SINTEF Ocean / Skip og havkonstruksjoner
  • Equinor
År
Forlag
The American Society of Mechanical Engineers (ASME)
Bok
32nd International Conference on Ocean, Offshore and Arctic Engineering Volume 1: Offshore Technology
Hefte nr.
1
ISBN
978-0-7918-5531-7