Based on the engineering background of the point-absorber wave energy converter (WEC), a variable-section float arm of the WEC is proposed. To obtain the basic mechanical properties of the structure under the wave load, the overlapping-grid technology is used to carry out the hydrodynamic analysis of the float by the commercial software STAR-CCM+, and the stress analyses of a constant-section float arm and a variable-section float arm are carried out by another commercial software ABAQUS. The results show that: both the stress peaks of the constant-section float arm and the variable-section float arm appear at the connection between the float arm and the base, where stress concentration is easy to happen. The float arm should be reinforced here in the design and manufacture. The stress peak and deflection peak of the variable-section float arm proposed in the present study are lower than those of the constant-section float arm. The high-stress area of the variable-section float arm is smaller than that of the constant-section float arm, and the stress distribution is effectively improved. Compared with the constant-section float arm, the variable-section float arm has better bending resistance and reliability, and can adapt to a more complex marine environment.
In recent years, the rapid development of population and economy has brought benefits to human beings, but also caused many problems. Among them, the problems of excessive resource consumption increasingly depleted energy and environmental pollution can not be ignored. Therefore, renewable energy is actively developed and utilized all over the world, among which ocean energy is an inexhaustible and clean new energy. China has a long coastline, wide marine land, and rich marine resources. The power load especially in the eastern coastal areas can create conditions for the development and utilization of large-scale ocean energy (Wang et al., 2014). As a kind of ocean energy, wave energy has an optimistic development prospect. It is estimated that the potential worldwide wave power resource is 2.0 TW (Drew et al., 2016).
