Numerical Simulation Of The Hydrodynamic Behaviour Of The Truncated Cone Fishing Cage In Current

The demands of fishery products are growing up with the increasing world population. And the people frequently enjoy themselves in the offshore. Then the development of the offshore aquaculture is faced with stagnation. It is unallowable that the offshore farming brings serious pollution. Therefore the aquaculture must be put into the open sea. Because of the higher speed ocean current and strong sea storm in the open ocean area, the cage volume used to farm fish will sharply decrease and the cage system get destroyed on the effect of the ocean current, as well as it will do great harm to the fish in the cage. So the key factor of the problem is to develop the anti-current and anti-storm capability of the fish cages for aquaculture engineering.In the dissertation, a numerical model of the truncated cone fishing cage is developed, based on lumped mass method. Based on the numerical model, an easy-to-use computer-simulation system for designing the truncated cone fishing cage is set up to reduce costs, save time, and avoid the labor of flume tank tests.The contents of the dissertation are mainly composed of five parts. In the first part, the author gives a general introduction of the background of the research and relative researches. The second part introduces the development and prospects of open ocean aquaculture industry and the common structure types. The second part is about the description of basic numerical method and theory, which will be applied in the following chapters. In the fourth part, the numerical simulations of the truncated cone fishing net are carried out in current. Consideration of different velocity, different weight mode, different RDH, different mesh type, compare and analysis the results of two types of cage. Finally the conclusion is given, and prospects of open ocean fish cage are discussed.