Study On Resistance Performance Of Fishing Boat Based On CFD

The number of fishing ships in China is large,most of them are mass fishing boats.The small and medium fishing boat means that the length of the fishing boat is not more than 25 meters,and the power is less than 400 horsepower.In general,the people about 5~12 work with the same ship,and the operation area is the coastal and offshore areas.When the small and medium fishing boats are working in the sea,the load of the boat is changed greatly.At the same time,it is necessary to ensure that the small and medium fishing boats can content the complex and changeable sea conditions at sea.Therefore,the performance of the fishing boats is higher.The speediness of the fishing boat is of great significance for the fishermen.It not only affects the time of the fishing boats arriving at the fishing grounds and returning to the wharf,but also affects the freshness of the fishing products,thus it affects the economy of the fishing boats.The rapidity of ships includes two aspects of ship resistance and ship propulsion.The resistance of small and medium fishing boats in the study is of great significance to the improvement of the rapidity of the fishing boats.In recent years,with the development of computer technology,CFD has been used more and more widely in the field of ship,and based on CFD,the study on the performance of ships has became more and more prominent.In this article,the author regards fishing boat as an object of study,the author makes models to simulate the resistance of fishing boat based on CFD.First of all,CFD is used to simulate to obtain the resistance of the fishing boat under different Fr,compare it with the resistance values of 1957 ITTC to verify its correctness.Secondly,the simulation analysis of the flow field around small and medium-sized fishing boats shows that the velocity and pressure of small and fishing boats are changed at different flow rates.At the same time,a specific flow velocity is given,the angle of flow direction is changed,and the flow field around fishing boats changes accordingly,which affects the stability of small and fishing boats.And then,under the action of dynamic waves,the velocity of the flow field changes at a constant speed.Under the condition of the same change in velocity and different time,the resistance value of the fishing boats is also different.The last but not the least,based on CFD method,the air and water two phase flow with free surface to carry on the numerical simulation,calculation of water resistance and air resistance coupling under the action of fishing vessels by resistance,the resistance value of air resistance and water resistance and separate role of comparative analysis,and explains the reasons for this phenomenon.