Computational Fluid Dynamics

CFD is an abbreviation for Computational Fluid Dynamics and generally refers to numerical analysis of fluids, including air and water. The difference between these and traditional methods, such as panel methods, is that CFD fully accounts for viscosity and the effects that arise from it. CFD requires significant computational resources, as well as specialised engineers and software. However, its usage is on the rise in the marine industry, due to ever-decreasing cost of computational power and better software that allows quicker setup of increasingly complex simulations. Typically, CFD fills the gap between model testing and traditional methods, where model tests are too expensive but traditional methods are too inaccurate. 


›  DOF/Semar – Forces on aquaculture structures – 2017

›  DOF/Semar – Moonpool XT deployment evaluation – 2016

›  Statoil – Drag on modified Jack-up Rig – 2016

›  Statoil – Motion damping on modified Jack-up Rig – 2016

›  Nymo – Roll damping on barge with non-standard bilge – 2015

›  DOF/Semar – Thruster effectiveness reduction on semi-submersible – 2015

›  DOF/Semar – Splash zone evaluation of subsea hatch – 2015

Areas of competence

›  Splash zone evaluation

›  Vessel Motion damping, decay tests

›  Hydrodynamic Coefficients: forced oscillation tests, drag, Added mass, slamming

›  Current and towing forces

›  Numerical model validation against experiments

Haven at Johan Sverdrup

Haven at Johan Sverdrup

The modifications made to Haven for it to be able to stand on the Johan Sverdrup field were significant, and these had an effect on the overall hydrodynamic behavior of the vessel. Adding 25m high footings, with a dry total weight of  8 000t, were expected to affect the motion of the rig. CFD analyses were performed to identify perturbations created by the footings and quantify crucial aspects such as damping and towing resistance.

Scope of work summary

›  Validation using previous model tests

›  Calculation of motion damping during tow

›  Calculation of motion damping during landing phase

›  Calculation of towing resistance for vessel

›  Evaluation of suction caisson towing

Key data

Mesh size 27M Cells
Simulation duration 6 days
Computational power Run locally on 28 core cluster
Simulation files size​​ >2 TB of simulation files generated