Study On Interaction Mode Between Ice And Propeller

During the navigation of polar ships,the interaction between propeller and ice will seriously affect the hydrodynamic performance of the propeller and even cause deformation or damage of the blade.In order to find out the effect of ice load on the hydrodynamic performance of the propeller and effectively reduce the effect of ice load on the blades,a series of freezing model ice experiments were designed and performed in the ice engineering laboratory of Tianjin University.The main factors affecting the performance of the propeller are:propeller diameter D,rotation speed n,advance velocity V_A,water densityρ,viscosity coefficientμ,and very special and complex ice material properties.The following three parts of the specific research work were carried out:(1)In order to explore the influence of the ice milling process on the hydrodynamic performance of the propeller,the model test under different cutting depths of the propeller was carried out under the condition of the change of the advance coefficient J=0.062-0.556.The relationship between the hydrodynamic performance(K_T and K_Q)of the propeller and the change of the advance coefficient,and the relationship between the hydrodynamic performance and the depth of the ice cutting are clarified.(2)In order to investigate the load condition of the propeller blades under the typical navigation conditions of the polar ship,the case of the advancing coefficient J=0.062 in the model test is analyzed,and then the axial load and tangential loads on the blades are estimated.(3)Based on the time-history curve of the change of load,the dynamic process of the generation and expansion of the ice damage field and the corresponding blade load are discussed.The interaction mechanism between ice and propeller is discussed.Based on the study of the three parts related to the interaction of the ice propeller,the influence of the hydrodynamic force and the load on the propeller under the condition of ice load is obtained,and the competitive relationship between the ice damage modes of ice propeller is discussed.This has certain reference significance for the subsequent hydrodynamic performance design and strength design issues of the ice propellers.