In order to adapt to the offshore extreme environment, a new semisubmersible offshore aquaculture platform is emerged. In this study, a series of experiments were carried out in the wave-current flume to study the motion responses of this aquaculture platform. According to the experimental data, the motion response including heave, surge and pitch had an upward trend with the wave height increasing. However, there was no obvious correlation between the motion response and wave periods. It can be concluded that wave parameters and draught should be taken into consideration in the structural design and optimization to guarantee the capacity of aquaculture platform to resist destruction in intense waves.
With the improvement of people's living standard and the increasing demand for sea food, marine aquaculture has become an important industry. However, traditional aquaculture facilities are easily destroyed and can not be used on a large scale to deep sea under strong currents and waves. Meanwhile, the increase of coastal aquaculture facilities has results in water pollution and produced a great damage to the environment. Thereby, it is urgent to develop a new aquaculture facility to apply to the open sea. Recently, Norway designed a new offshore aquaculture platform, Ocean Farm 1, which has been built in China (SalMar, 2018). This novel aquaculture platform may lead the aquaculture platform to a new era and provide a new aquaculture model.
Hydrodynamic responses of traditional fish cage including experimental and numerical studies have been widely investigated by many researchers. Chen et al. (2009, 2012) applied the lumped mass method and rigid kinematics theory to simulate the gravity cage in waves and used the Runge-Kutta fifth-order method to solve motion equations. Zhao et al. (2013) analyzed the motion of a box-shaped net by numerical and experimental method in pure waves and the numerical results agreed well with the data obtained from physical model test. Xu et al. (2013) proposed a numerical model to simulate the motion response of submersible net cage and conducted a series of tests to validate the numerical results in waves. Li et al. (2013a, 2013b) used the beam element, truss element and spring element to simulate the floater, net and mooring line, respectively, and then the motion and deformation of the fish cage were investigated in regular waves and irregular waves. James et al. (2015) carried out a series of model and prototype experiments to analysis the motions of marine culture cage. Bi et al. (2015) studied the damping effect of net cages in waves and analyzed the wave transmission coefficient of net cage in different wave periods, wave heights, numbers of net cages, net solidities, measurement positions, geometrical shapes of the net cages and Reynolds numbers. Kristiansen et al. (2015) adopted experimental and numerical method to investigate main factors affecting mooring loads and the validity of different rational hydrodynamic load models. Cifuentes et al. (2017) discussed the hydrodynamic response of cage system under combinations of current and wave loading based on a Morison-force model, and then the numerical results were compared with experimental data.
