The mathematical model is based on a time-step solution of the system of coupled differential equations of motion. Vessel specific results from linear diffraction calculations, consisting of frequency dependent wave forces, added mass and damping are typically used to model the hydrodynamics. The impulse response method is then applied to determine the time domain response. Other elements such as rudders, propellers, mooring lines, fenders, thrusters, etc are modelled in time domain. Depending on the application, one of the available generic solvers is used to solve the equations of motions.


Reliable physics modelling is the main objective of aNySIM XMF. Validation and verification are an essential part of the development. aNySIM XMF is developed by implementing the functionalities systematically making sure that every step is verified and benchmarked against analytic solutions. Furthermore, a unique benefits of aNySIM XMF is its validation against high quality model test, full scale trials and other simulation software. This feature is not easily found in other competing software.


A project-based version of aNySIM XMF (called aNySIMpro) is available. In this case, MARIN prepares the initial set-up of the project-based aNySIMpro. Further information about the possibilities can be found in the aNySIMpro leaflet. Often, after a project-based aNySIMpro, the user decides to become a member of the aNySIM User Group. Members of the User Group express the intention to be long-term users. During User Group Meetings, experience is exchanged and future developments are discussed. Members of the User Group have a voice in the course of the developments. Current members are Bluewater, GustoMSC, Heerema, Royal Haskoning DHV, Saipem and Shell.
Turning circle in waves
A naval hull performing a turning circle in irregular waves and wind with aNySIM. The manoeuvring forces are based on a set of tuned coefficients from captive model tests, while the seakeeping forces are based on Rankine calculations using SEACAL.
Side-by-side offloading operation
When two vessels are in close proximity, it is necessary to take the hydrodynamic interaction of the bodies into account. Therefore one hydrodynamic database of both vessels is created with a damping lid between the vessels to suppress unrealistic wave oscillations. The two vessels are connected with fenders and lines for the side-by-side offloading operation. Typically a large batch (>100,000) is run to determine the operability of the operation at the site.
Floating mega island
The floating mega island consists of 87 large, floating triangles that are connected with lines and fenders to one another. Together they form a flexible island that can be as large as 1-5 km in cross-section Numerical calculations are performed with aNySIM to predict the motions and loads of the triangles and to optimize the size and weight of the island modules.
Hydro-elastic model of a fish farm
Hydrodynamic loads on the nets are included through an interactive coupling with our CFD codes. CFD provides the drag loads on the nets, while the time domain software aNySIM determines the hydro-elastic motion response. The coupled numerical models enable the loads on and motion behaviour of fish farm constructions to be determined.