Abstract:To acquire the actual wave force on an artificial reef under wave action and verify the stability of the artificial reef at the bottom of the sea, the influences of various nonlinear factors on the wave force acting on the artificial reef and numerical computation method for wave force should be analyzed and obtained. In this study, the nonlinear characteristic of the Morison equation for the horizontal wave force was analyzed using the dimensionless method based on the second-order Stokes wave theory. In addition, based on the computational fluid dynamics and finite volume method, adopting the Boundary wave method, a 3D numerical wave tank was established by the volume of fluid method. On account of the numerical results, the optimized relational expression of the maximum wave force and wave steepness was fitted by linear regression analysis method. The optimum equations of the maximum positive/negative horizontal force (Fmax/F–max) and wave steepness (δ) were Fmax = –0.89 + 110.44δ and F–max = –0.10–83.52δ, and the correlation coefficients were 0.9795 and 0.9899, respectively. The coefficient of anti-rolling and coefficient of anti-slide were 2.11 and 3.96, respectively, under the action of waves with the largest wave steepness. The results indicated that the main non-linear factor for the horizontal wave force acting on the artificial reef was wave steepness and the nonlinear effect enhances with increase in the number value. Taking a type of frustum cones artificial reef as an example, the maximum positive and negative horizontal wave force and the corresponding wave and pressure fields around the artificial reef were obtained. According to the numerical simulation results, the horizontal wave force of the artificial reef appeared to change periodically along with wave motion and increased with wave steepness. The results of stability calibration showed that the frustum cones artificial reef remained fairly stable on the sea floor at different test conditions, and it is well suited to the much larger wave heights in the sea.
