Wave Drift Force - Newman’s method Calculation of wave drift forces from wave drift force coefficients using Newman’s method (approximation). The wave drift force coefficients corresponds to the frequency diagonal of the difference-frequency quadratic transfer function. See also Simplified wave drift force model. By checking the Enable wave-current interaction checkbox, the zero-current wave drift force coefficients will be modified using Aranha’s formula at the time of running a simulation, based on the actual current velocity and direction. The corrected wave drift force coefficients 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. When Newman’s approximation is not valid, a full Difference-Frequency QTF should be used instead. Soil Penetration Wave Drift Force - from full Difference-Frequency Quadratic Transfer Function (QTF)