船舶尾部避振穴的设计研究

Design of anti-vibration cave at ship stern

避振穴是一种能有效减小船舶尾部振动的密闭充气结构。基于振动学和板壳结构的相关理论,推导了避振穴橡胶板固有频率的近似计算方法,结合参考文献和非线性有限元计算对理论计算方法进行了验证,总结了各设计参数对固有频率的影响;基于两自由度(DOFs)振动系统,分析避振穴固有频率对减振效果的影响,讨论避振穴设计过程中需要考虑的因素;针对某318000 DWT超大型油轮进行尾部避振穴的设计,对比加装避振穴前后船体的响应特性,验证避振穴的减振效果。对避振穴的频率特性和设计参数的选取进行了较为详细的分析,可为相关的减振设计提供有益参考。

The anti-vibration cave is a closed air-filled structure being able to effectively reduce vibration at ship stern.Here,based on the vibration theory and the theory of plate and shell structures,the approximate calculation method of natural frequency for anti-vibration cave rubber plate was deduced.The theoretical calculation method was verified with reference literature and nonlinear finite element calculation.Effects of design parameters on natural frequency were summarized.Then,based on the theory of 2 degree-of-freedoms(DOFs)vibration system,effects of anti-vibration cave’s natural frequency on vibration reduction effect were analyzed,and the factors to be considered in design of anti-vibration cave were discussed.Finally,the design of anti-vibration cave at ship stern was performed for a 318000 DWT super-large tanker.The response characteristics of the ship before and after retrofitting anti-vibration cave were compared to verify the vibration reduction effect of anti-vibration cave.Anti-vibration cave’s frequency characteristics and design parameters selection were analyzed in detail here.It was shown that the study can provide a reference for relevant vibration reduction designs.