...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Ocean Engineering >Identification of the nonlinear roll damping and restoring moment of a FPSO using Hilbert transform
【24h】

Identification of the nonlinear roll damping and restoring moment of a FPSO using Hilbert transform

机译：使用希尔伯特变换识别FPSO的非线性侧倾阻尼和恢复力矩

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Roll motion is a major concern of ship and offshore operators because it has a direct impact on the boarding comfort of crews, downtime of the process plant and structural integrity of the hull and appurtenance system. Nevertheless, the nonlinear effects involved in the roll motion of ship and offshore structures are not only incompletely understood, but also inaccurately predicted during the design stage. Therefore, efforts have been made to identify the dynamic characteristics of the roll motion of a FPSO using a novel dynamic system identification scheme based upon the Hilbert transform. First, the system identification scheme using the Hilbert transform was applied to the idealized single DOF nonlinear oscillator problem with quadratic damping and quintic stiffness terms. The solution of the single DOF problem was solved numerically using the 4th order Runge-Kutta method and the target damping and stiffness coefficients were determined by applying the Hilbert transform to the numerically obtained free decay signal. A comparison was also made with traditional logarithmic decrement technique for the damping coefficient. Second, the system identification method was applied to the model test results of a FPSO with a bilge keel, where the nonlinear effect of roll damping and restoring is expected to be dominant. This methodology can be applied to full scale measurement data to achieve a clearer understanding on the nonlinear effect of roll motion. (C) 2015 Elsevier Ltd. All rights reserved.
机译：横摇运动是船舶和近海操作者的主要关注问题，因为它直接影响船员的上船舒适度，加工厂的停工时间以及船体和附属系统的结构完整性。然而，不仅不能完全理解船舶和海上结构的滚动运动所涉及的非线性效应，而且在设计阶段还不能准确地预测非线性效应。因此，已经做出了努力来使用基于希尔伯特变换的新颖的动态系统识别方案来识别FPSO滚动运动的动态特性。首先，将使用希尔伯特变换的系统识别方案应用于具有二次阻尼和五次刚度项的理想单自由度非线性振荡器问题。使用四阶Runge-Kutta方法以数值方式解决了单个自由度问题的解决方案，并通过将Hilbert变换应用于数值获得的自由衰减信号来确定目标阻尼和刚度系数。还与传统对数递减技术的阻尼系数进行了比较。其次，将系统识别方法应用于带有船底龙骨的FPSO的模型测试结果中，其中侧倾阻尼和恢复的非线性效应预计将占主导地位。该方法可以应用于满量程测量数据，以更清楚地了解横摇运动的非线性影响。 （C）2015 Elsevier Ltd.保留所有权利。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号