Study On Hydrodynamic Performance Of Trawler Considering Fishing Gear Influence

With the progress of era and the change of the fishery resources,the fishing ship will develop into the direction of ocean operation,large scale,high efficiency and energy saving.Trawler is one of the most common fishing boat in fishing industry,so it's significant to study on the hull hydrodynamic performance,which can provide theoretical basis for the development of fishing efficiency and economy.In this paper,the hydrodynamic performance of 42 m trawler in trawling condition is studied.The main contents include the feasibility of numerical simulation,ship model pool experiment and numerical simulation.First,the feasibility of numerical simulation of hull resistance is studied.The feasibility of numerical simulation is verified by comparing the experimental results and numerical simulation results under the same operating conditions.Second,the ship model resistance pool experiment considering fishing gear effect is carried out.The effect of fishing gear in working condition on hull performance is mainly reflected in the change of resistance in the horizontal direction and the hull trim angle.so this paper selects five different trim angle,each trim angle as a kind of condition,and one condition containing five speeds.And ship model resistance experiment is carried out for each working condition.Third,the numerical simulations are carried out under the same conditions,and getting the hull resistance changes and the velocity and pressure contours on free surface,etc.The conclusion accuracy is validated by comparing the numerical simulation result and the experiment result.And the hydrodynamic performance of the trawler during the trawl operation is obtained.By comparing the simulation data and the experimental data,it is feasible to simulate the ship model resistance with FLUENT software,and the law of hull resistance between velocity and trim angle is obtained.At the same trim angle,the hull resistance will increase while the speed increasing;at the same speed,the hull resistance will increase with the increase of the trim angle.In addition,the hull streamlines and the pressure and velocity contours on free surface under different conditions and speeds are obtained.