Hydrodynamic Behaviour of a Floating Linkspan: A study on wave responses
Typ
Examensarbete för masterexamen
Program
Applied mechanics (MPAME), MSc
Publicerad
2021
Författare
Amiri, Yousef
Sheikholeslami, Pouya
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
Maritime transport is an important part of global trade. Ro-Ro transports standing for roll-on-roll-
off is a an important part of maritime transport. Ro-Ro transports is closely related to the
concept of linkspan. Tide and waves can make access to quay difficult. A linkspan, as a solution
is a facility to provide a good connection between shore and ship for discharging and loading.
In this thesis firstly, a hydrodynamic study is performed on an integral tank linkspan to understand
how environmental factors such as wave at extreme tide levels (Highest and Lowest Astronomical
Tide) in combination with extreme loading conditions (Full and Empty) affect the motion of the
linkspan. Secondly, a load mapping approach is performed to study the wave impacts from a
structural strength perspective. This approach is based on using inertia information from the
hydrodynamic or the structural model, since these are not the same. The feasibility of the load
mapping approach is also assessed.
Heave and pitch motion is studied in head sea (180 wave heading angle) while roll motion is studied
in beam sea (90 wave heading angle) in the hydrodynamic analysis. The results have shown that
at small wave periods the pitch motion is unfavorable at the highest tide level. Maximum roll
motion is obtained at smaller wavelength to structure length ratio in comparison to the heave
motion.
The load mapping reflects the wave situation fairly good and the wave impact can be reflected in
the deformation contour-plots. It is found that the maximum stress in the load mapping part is
obtained at the hinges. It is also found that by using inertia from structural model a more realistic
result in terms of deformation is obtained.
Beskrivning
Ämne/nyckelord
potential flow , Source Distribution Method , Ansys Aqwa , Response Amplitude Operator , Finite Element Method , incident wave , diffraction wave , radiation Wave , wave spectra , heave , pitch , roll.