Thanks for your reply. I’m worried about the calculation of the radiation loads. Although the constraints are established between two objects, the added mass and radiation damping coefficients are still obtained by exerting objects’ forced motion. The forced motion would cause narrow gap resonance phenomena. For exmaple, in the surge direction, the outer object is fixed and the inner object moves in a harmonic motion with unit amplitude. This will overestimate the radiation waves in the gap and cause strange peaks around resonant frequency in added mass and radiation damping. But in physics, such singular peaks do not exist due to constraints between two objects.
The incorrect radiation damping coefficients gererate the incorrect radiation impulse response function when convolution integral is activated. I’m worried that this will affect the time domain calculations. How AQWA solved the problem?