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Rankine panel methods have been studied for solving 3D seakeeping problems of a ship with forward speed and oscillatory motions. Nevertheless, there is a drawback in the numerical method for satisfying the radiation condition of outgoing waves at low frequencies, because the waves generated ahead of a ship reflect from the outward computational boundary and smear the flow around the ship. The so-called panel shift technique has been adopted in the frequency-domain Rankine panel method, which is effective when the generated waves propagate downstream of a ship. In this paper, in addition to this conventional panel shift method, Rayleigh’s artificial friction is introduced in the free-surface boundary condition to suppress longer wave components in a computational region apart from the ship. With this practical new method, it is shown that there is no prominent wave reflection from the side and/or upstream computational boundaries even in the range of low frequencies. As a consequence, the unsteady pressure, hydrodynamic forces, wave-induced ship motions, added resistance are computed with reasonable accuracy even in following waves and in good agreement with measured results in the experiment using a bulk carrier model which is also conducted for the present study.

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We observed that Compton-scattered photons are enhanced in a supercavity. We can increase the laser beam intensity in such a cavity and obtain a reasonable number of scattered photons. In our experiments, an e-beam of ∼82 keV and a 1 µ m wavelength laser beam were used in the supercavity. The storage rate of the supercavity was ∼4000 times. The wavelength of the scattered photons was calculated to be 364 nm and the flux to be approximately 400 [photons/s]. The experimental results agree well with the theoretical prediction.

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