Pipeline Layout Design And Resistance Analysis Of Through Flow Type Of Non-ballast Water Ship

Ship have played an important role in marine development,especially in water & energy transportation and national defense construction.When transporting over long distances,ship transportation is more economical than rail transportation.Especially when transporting bulk goods such as raw materials,the efficiency of loading and unloading can be improved by dedicated ship.Ship need ballast water to ensure their stability,the replacement of ballast water problems will cause ecology destruction and species proliferation when ship form one sea area to enter anther sea areas.At this moment,the imperfect ballast water treatment system leads to problems that the treated ballast water still does not under the standard.Therefore,the academic community has proposed the concept of non ballast water ship.So far,three type of non ballast water with the highest recognition have appeared in the world.One of the three ship types,the through-flow ship type first solved the problem of ballast water replacement for large ships,but this article applies the idea of through-flow innovatively to the fishing boat.This is because the fishing boat has a part of the fixed ballast.Whether the through-flow fishing boat can replace fixed fishing boat or not.Therefore,based on the CFD numerical simulation,this paper calculates the performance of the trawler,and compares the numerical calculation results of the mother ship and new ship to provide a theoretical basis for the optimization.First,it introduces the international and domestic research status of non-ballast water ships,the development history of fluid mechanics,and the status and research methods of ship resistance research.Secondly,the theoretical basis of ship resistance and the superiority of STAR-CCM + software in the meshing of complex curved surfaces are introduced.Then it introduces the main contents of CFD in more detail,including the derivation of control equations,the introduction of turbulence models commonly used in ships,the setting of numerical boundary conditions,the basic concepts of the finite volume method and the free water surface simulation VOF method.Thirdly,innovatively establish a model of through-flow non ballast fishing boat and lay out the design of through pipes.On the basis of ensuring the through-flow ballast-free watercraft type,verify the mother and new ship on the main scale through empirical formulas.The performance of the ship coefficient and stability and other aspects,preliminary judgment whether the new ship type meets the requirements of relevant practice.Finally,the STAR-CCM + software is used to analyze the resistance of the fishing boat under different working conditions.And the total resistance,frictional resistance,residual resistance,pitch and rise of the mother ship and the new ship under different working conditions are analyzed respectively,provide reference basis for the actual sailing ship.