Wave Drift Force - from full Difference-Frequency Quadratic Transfer Function (QTF) Calculation of wave drift forces from full Difference-Frequency Quadratic Transfer Function (QTF) See also Second-order wave forces. By checking the Enable wave-current interaction checkbox, the zero-current QTF will be modified using Aranha’s formula at the time of running a simulation, based on the actual current velocity and direction. The corrected QTF can be viewed in the wave-current correction preview. Note that the current velocity and direction entered in the previewer is only for the preview. In a simulation, the actual current condition is used. Note also that checking Enable wave-current interaction will only enable the excitation part of the wave-current interaction. To also include the damping effect due to body velocities, a wave drift damping model should be added. See also Wave-current correction of second order wave drift force and wave drift damping using an extended Aranha’s formula. Wave Drift Force - Newman’s method Wave Drift Damping - Newman’s method