Numerical Simulation And Experimental Validation On The Effect Of Netting Panels On The Wave Spread

With the increasing of human demand for fishery products, China’s fish farming has had great development. However, due to the overfishing of coastal fisheries resources and unreasonable development, coastal ecological environment deteriorated sharply, fishery resources has been almost exhausted, so the net cages for aquaculture from inshore to offshore area is overwhelming. But offshore deep-water aquaculture is facing a more hostile environment ordeal, due to the lack of production of breakwaters, under the action of strong wind and wave, the net cages vulnerable to damage and resulting in significant loss of fisheries, so the research of interaction between wave field and force on net cages is urgently needed to resolve.Domestic and international research on net cages mainly concentrated on the dynamic response and the force on mooring system under wave conditions, ignored the net panel effected on wave propagation, but the action between wave and net panel was mutual, the effect on wave dissipation of net panel were considerable. Aiming at the rarely research about wave hydrodynamic characteristic of net panel, the numerical wave tank was established based on the CFD methods, by using the porous media model to simulate the net panel, studied the net panel impacted on the wave form and wave propagation, calculated the force on net panel, analyzed the relationship of parameters of net panel, wave parameters and wave transmission coefficient. The numerical results were compared with the experimental results, and the accuracy and applicability of mathematical model was proved.This content consists of five parts. In the first chapter, the author briefly introduced the background of the research and the condition and development tendency of the research. The second chapter is about transformation of net panel to porous media model, the creation of mathematical model, the method of mesh dividing and the settings of boundary conditions, then, by the second development of FLUENT software, through setting the movement boundary as the wave board in the computational domain, the simulation of movement about wave generator in reality was completed. The third chapter is the validations and comparisons of results between numerical simulations and physical experiments, at first, the study of the single net panel impact on the wave form and wave propagation was completed, the results showed the force on net panel and wave transmission coefficient agreed well with the experimental data, the short-wave produced greater wave height attenuation, and the change of solidity ratio of nets didn’t have obvious effect on the wave spread. The fourth chapter is about the study of wave field on double net panels, the results showed that the change of distance between two net panels didn’t have obvious impact on wave propagation and the forces on net panels. The last chapter is summary and discussion of the research work, the author expounded the research achievement and limitation.