DIFFRAC

DIFFRAC is a wave diffraction program capable of calculating the first-order wave loads and motion responses of multi-body free floating or moored structures in regular waves, including their hydrodynamic interaction. DIFFRAC is also capable of calculating the mean and low-frequency second-order wave drift loads. The program is applicable to both shallow and deep water and has been validated against many physical model test results.

Contact

Frederick Jaouen

Senior Project Manager

The wave loads and resulting motions on multibody systems in waves can be calculated easily. There is no limitation on the number of bodies other than memory. Systems with more than 300 bodies have been calculated. The effect of the water depth and current are taken into account.

The wave loads and resulting motions on multibody systems in waves can be calculated easily. There is no limitation on the number of bodies other than memory. Systems with more than 300 bodies have been calculated. The effect of the water depth and current are taken into account.

The hydrodynamic loads applied on a multi-body system oscillating in calm water can be calculated easily for a wide range of frequencies. These hydrodynamic loads are reported as the added mass contribution and the potential damping contribution. The effect of the water depth and current are taken into account.

The hydrodynamic loads applied on a multi-body system oscillating in calm water can be calculated easily for a wide range of frequencies. These hydrodynamic loads are reported as the added mass contribution and the potential damping contribution. The effect of the water depth and current are taken into account.

The natural frequencies of a containment system can be calculated. A damping lid can be used to damp the amplitudes of these natural modes in order to account for the viscous damping in the system.

The natural frequencies of a containment system can be calculated. A damping lid can be used to damp the amplitudes of these natural modes in order to account for the viscous damping in the system.

Forced Oscillating LNGC in Calm Water

DIFFRAC calculates the hydrodynamic loads applied on offshore structures oscillating in calm water. These radiation calculations lead to hydrodynamic coefficients , also referred to as added mass and potential damping coefficients.

LNGC in Bow-Quartering Waves

DIFFRAC calculates the motions of offshore structures in regular waves. As an illustration, this movies shows the motions of a LNG Carrier in a bow-quartering wave with period of 7sec.

LNGC in Beam-On Waves at Roll Resonance Period

DIFFRAC calculates the motions of offshore structures in regular waves. As an illustration, this movies shows the motions of a LNG Carrier in a beam-on wave with bow-quartering wave with period of 18sec. The motions of the vessel are large because the wave period corresponds to the natural period of the vessel, and the roll damping of potential nature is included only in this specific example. By including some viscous damping, the motions will significantly decrease.

Partners willing to collaborate with us and use DIFFRAC can become part of the DIFFRAC User Group. This comes with an unlimited number of parallel users, cpu cores and parallel computations. 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.

Downloads

Leaflet DIFFRAC (PDF)