Dynamic Response Analysis Of Valve Subjected To Different Excitation In Ship

The vibration and shock resistance of shipboard pipeline system are key factors for ship survival. As an important part of the pipeline system, valve is more likely to be susceptible to the vibration load and shock load due to its large size and high gravity center. If valve in critical positions like gas turbine failed, there is a chance to cause medium leakage, or even the loss of warship force, which makes the analysis on vibration and shock resistance of warship valves significant.In this thesis, researches on dynamic responses of warship valve under vibration loads and shock loads are conducted by using ANSYS software based on the warship valve installation and structural characteristics, under the help of relevant theories to warship equipment vibration and shock resistance, the regulated loads in relevant standards and the numerical methods of shock resistance analysis for warship equipment. Finally, the results can provide reference for the vibration and shock resistance studies on warship valves.First, based on the modal analysis theory, the natural frequency and vibration mode of valve were analyzed by using FEM software through frame modeling analysis and constraint modeling analysis. The result showed that the deformation of stem and bonnet was visible and their stiffness was weak.Then based on the regulated vibration loads and condition, the vibration equation for valve was built. The harmonic response of valve was analyzed by using ANSYS Workbench. The results were coincided with theoretical vibration response function curves. The stress and strain of all important parts were analyzed thereafter. We found out the severe vibration area of the valve in normal working state and then attempted to optimize it. The analysis results showed that increasing the size of the bracket is easy to change the vibration response of cut-off valve.Finally, after the theoretical analysis on the three methods for analyzing the shock resistance of warship equipment was finished, the time domain simulation method was chose. Through the time domain method, a series of operating conditions were designed for German army mark BV043-85, and numerical impact tests were conducted on the model of valve for the analyzing on the laws of shock response and impact resistance capabilities of the valve from all directions. The results showed that the shock resistance on longitudinal direction was the worst. According to the main influential factors, this thesis provided suggestions for improving shock resistance of warship.