Hydrodynamic Analyze Of Floating Perforated Structures Based On 3-D Potential Theory In Frequency Domain

Perforated structures are widely used in ocean engineering,as they can significantly dissipate energy of waves and reduce wave force of structures.So,it is necessary to develop a hydrodynamic analysis method of perforated structures,which is efficient and accurate.This paper aims at establishing a hydrodynamic analysis model of floating perforated structures based on potential theory in frequency domain.There are obvious flow separation nearby perforated structures,so it is complex to simulate the flow situations directly in these fields.Matching conditions of perforated wall,which describes the relationship between pressure drop and normal flow velocity,are normally used to represent the flow energy dissipation caused by perforated wall.In this paper,the matching condition of perforated wall is briefly introduced,and the governing equation of floating perforated structure is given based on the matching condition of perforated wall.In numerical method,1st order Taylor Expansion Boundary Element Method(TEBEM)is used to increase the accuracy of tangential induced velocity at sharp corners,which will increase the accuracy of mean drift force of floating bodies with sharp corners.In this paper,two kinds of boundary integral equation of floating perforated bodies based on 1st TEBEM are proposed.The effect of porosity on the wave excitation force and hydrodynamic coefficient of a sidewall perforated cylinder is studied.The numerical results are confirmed by experimental results.The effect of porosity on the mean drift force of a sidewall perforated cylinder is also studied.The numerical results indicate that mean drift force decreases with the increase of porosity.The hydrodynamic performance and wave dissipation ability of floating perforated breakwater are studied in this paper.The effect of structure types and porosity are considered.The numerical results indicate that the flow energy dissipation capability of perforated structures will be more significant in domain with high flow velocity.