| Abstract: | Helicopter rescue has become an important way of life and property relief in modern society.The structure and parameters of the helicopter hoist bracket influence the convenience,safety and reliability of the rescue operation for the lifeguard and hoistman.Based on fatigue analysis theory and ANSYS workbench software,the fatigue life analysis of the hoist bracket is carried out.First,the structure of the hoist bracket is modeled according to the body standard of the hoistman and lifeguard.Then an approach is presented to obtain the S-N curve of the hoist bracket by modifying the S-N curve of the bracket material based on Goodman curve while considering the influences of the shape,size,surface state,loading conditions and the average stress.Further,based on the ANSYS workbench analysis,the life and safety nephogram of the bracket under the fluctuating cyclic load can be obtained.Finally,the designed bracket is analyzed with the proposed method.The cycles number of the bracket is greater than 107 under the extreme conditions of the pulsating cyclic load,which may be considered as the unlimited life and meets the requirement of the fatigue strength. |
