Study Of Response Characteristics Of The Strut Bearing Under The Underwater Explosion Shocks

Marine power system is an important part of the Marine equipment system. Its comprehensive performance often directly affects the survivability of the ship. Ships sailing in the actual working process are likely to encounter various explosion shocks. As one of the vulnerable parts of the ship power system, strut bearings are completely soaked in water. So strut bearings are easily affected by external environment. Then, when the underwater explosion load shocks on strut bearings, the damage of strut bearings will be more serious. So researching on the response characteristic and the shock resistance of strut bearings shocked by the non-contact underwater explosion load can ensure strut bearings’ stability and safety, which can has very important application value of the ship.This paper systematically studied the related theory of underwater explosion shock, and utilizes the large finite element simulation software ANSYS/LS-DYNA to analyze the vibration characteristics of strut bearings, the response characteristics of strut bearings shocked by underwater explosion load and the effect of different explosion conditions to the response characteristics of strut bearings. Specific work content is as follows:(1) Based on underwater explosion theories, this paper expounds the basic theory and characteristics of underwater explosion, analyses the mechanism and characteristics of bubble motion and its fluctuating pressure. Expound the characteristics of underwater explosion shock wave, and give the half experience and half theory calculation formula of the pressure peak of underwater explosion shock wave. At the same time, simulate the environment of underwater explosion and the spread of explosion shock wave, and use the empirical formula to verify the feasibility and reliability of the numerical simulation results, which prepare for the back research work.(2) Establish the finite element model of the strut bearing. Analyze the free vibration of the strut bearing to conclude natural frequency and vibration characteristics of the strut bearing. At the same time, analyze the response characteristics of the strut bearing shocked by non-contact underwater explosion. Calculate the parameter change rule of the strut bearing shocked by non-contact underwater explosion, such as displacement, stress, velocity and acceleration.(3) Study the response characteristics of the strut bearing under different explosion conditions. Discuss the factors and the parameter change law of the strut bearing shocked by underwater explosion load. These factors contain the explosive equivalent and the burst position. The results show that the explosive equivalent and the burst position of will affect the response characteristic of the strut bearing dramatically. These results can provide certain auxiliary for the future design and explosion shock strut bearings damage prediction research.