基于虚拟质量法的高速船总振动直接计算

Direct Calculation of Overall Vibration of High Speed Ship Based on Virtual Mass Method

考虑到船舶总振动计算时,附连水质量的计算方法直接关系到总振动计算精度,以某高速船为例,采用有限元分析软件MSC.PATRAN/NASTRAN进行总振动特性计算分析,介绍有限元模型建立、非结构重量模拟,以及重量重心调整,重点分析虚拟质量法在附连水质量计算中的应用,计算结果表明,该船的总振动频率储备满足相关规范的要求;实船使用验证表明,4种典型工况下均未发现全船性的明显振动,基于虚拟质量法的高速船总振动计算结果可靠,可满足工程计算要求。

The method of the added mass directly affects the calculation precision of the overall vibration.Taking a high speed ship as example,modal analysis was carried out for overall hull structure by MSC.Patran/Nastran.The establishment of finite element model,simulation of non-structural weight,and adjustment of weight and center of gravity were introduced,focusing on the application of virtual mass method in the simulation of added mass.The numerical results showed that the overall vibration frequency reservation of the ship satisfies the requirement of relevant rule.The practical application of the ship verifies that the obvious vibration was not appeared in 4 typical cases,so that the overall vibration calculation of high speed ship based on virtual mass method is highly reliable and the results can satisfy the engineering needs.