Numerical Analysis On Shock Resistance For Retraction Equipment On Surface Ship

Retraction equipment is an important part of the underwater towing system for ships.The shock-resistance ability plays a significant role in towed sonar system, acoustic warfaresystem and minesweeping system using on underwater defense and anti-submarine war. Thispaper focuses on the retraction equipment and a integral finite element model is established.The shock response in vertical, longitudinal and lateral are calculated with the time-domainsimulation method and sub-model method. Based on the partial shock response got from thecalculation, the strength of the bolts using for the connection between the retractionequipment and the foundation are checked with empirical formula method. The stressdistribution of the whole model and acceleration response of the gear, bearing and drivingmotor in the propulsion system transmitted by gears are obtained during the study. The resultscan provide reference data for the following calculation of these structures.Following aspects are included in this paper. Firstly, on the basis of the analysis andsimplification for the geometric model of the retraction equipment, the integral finite elementmodel is established. Secondly, the basic theories of shock spectrum and time-domainsimulation method using in the shock computing for ships are researched. The shock load istransformed into double sinusoidal course with equivalent simplified method and applied tothe retraction equipment. Thirdly, the stress distribution of the whole model and accelerationresponse of the gear, bearing and driving motor in the propulsion system transmitted by gearsare calculated and analyzed. The results can provide reference data for the followingcalculation of these structures. Fourthly, the stress distribution between track and wheels iscalculated further because that the area between track and wheels is so small and the elementsize has a great influence on the stress distribution during the vertical shock. Finally, thestrength of the bolts using for the connection between the retraction equipment and thefoundation are checked with empirical formula method because that the geometric model ofbolts are unknown.