Numerical Analysis Of Ice Load On Polar Ship And Propulsion Device

Recent years,with the international community on the Arctic channel and polar resources mining attention gradually increased,the ice ship research has received more attention and has made considerable development.In the ice area,the operating conditions of the ship are quite different from those of the conventional ships.Especially in the icebreaking state,the icebreaker will be subject to larger ice breaking resistance and have a great influence on the hull sailing performance.Then part of the crushed ice will be immersed under the surface of the hull to the bottom of the ship,and slide into the propeller front flow field,with the stern of the propeller milling collision,the propeller shows the ice load,affecting the hydrodynamic performance of the paddle.Then,the ice load on the blade is transmitted to the other components of the propulsion system through the propeller shaft,which has a greater impact on the entire shaft.In order to investigate the influence of ice resistance and fluid resistance on the ship's s continuous ice-breaking and collision-ice-breaking,the influence of speed and ice thickness is discussed.Firstly,the ship-ice-flow coupling model was established by using the dynamic software LS-DYNA,and the ice resistance,water resistance and ice damage of the ice hull under different ice speed were analyzed.During the ice-breaking process,the ice has obvious damage to the fracture,and in the hull and the ship has a large number of crushed ice accumulation.It is found that the ice resistance of the icebreaker increases with the increase of the speed and increases with the increase of the ice thickness.For the fluid resistance,the numerical change has little effect on the resistance of the ice with the change of the ice thickness.Further analysis of some crushed ice into the bottom of the collision with the propeller milling,the use of SPH particles to simulate sea ice,ice-propeller-flow numerical calculation.Before and after calculation,the mechanical properties of sea ice under tensile failure and compression failure were introduced.The sea ice crack initiation and expansion forms were analyzed under uniaxial loading,biaxial loading and triaxial loading.The numerical simulation results of this section show that the numerical simulation results are in good agreement with the experimental results and have certain significance.Then the Rage ice paddle model was used to establish the three-dimensional model,and the analysis of the ice-paddle milling process in the sea ice's failure mode propeller showed the stress concentration phenomenon.On this basis,the three milling depths were changed,and the nine milling factors were calculated.The relationship between the contact coefficient of the ice pad and the torque coefficient of the ice load and the speed of the ice load is plotted,and the calculation trend is compared with the large side oblique paddle.The results show that the size of the ice load increases with the increase of the milling depth.When the velocity coefficient increases with the increase of the speed coefficient,the ice load increases with the velocity coefficient Increase and decrease.In order to analyze the effect of the ice load on the propeller and the propeller shaft.The static and dynamic analysis of a paddle shaft was carried out by explicit implicit combined method.In this paper,the propeller shaft is calculated and calculated,and the results such as the reaction force,shear force,bending moment and deflection of each bearing are calculated.Then,the stiffness and the support point of the rear bracket bearing are further analyzed on the shaft uniform force of the impact of the shaft for the reasonable design to provide support.On the basis of this,the numerical simulation of the parameters of the ice paddle is carried out by the display dynamic method.The variable parameters mainly include the change of the radial position of the sea ice,the change of the sea ice size and the change of the sea ice velocity,and then extract the total load Axial force,vertical force,axial bending moment,horizontal bending moment.In the Abquas software,the four ice loads were fed to one end of the propeller shaft to analyze the impulse response of the propeller shaft.The results show that the generation of ice load will produce a large reaction force,displacement response,torque response and stress change to the rear bracket bearing near one end of the propeller.The displacement and equivalent stress and torque of the shaft system increase with the decrease of the radial distance of the sea ice and increase with the increase of the sea ice size.The faster the sea ice is,the greater the damage is.