• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>International Conference on Offshore Mechanics and Arctic Engineering 2007(OMAE2007) vol.4; 20070610-15; San Deigo,CA(US) >THE EFFECT OF BOW SHAPE ON THE SPRINGING/WHIPPING RESPONSE OF A LARGE OCEAN-GOING VESSEL - INVESTIGATED BY AN EXPERIMENTAL METHOD
【24h】

THE EFFECT OF BOW SHAPE ON THE SPRINGING/WHIPPING RESPONSE OF A LARGE OCEAN-GOING VESSEL - INVESTIGATED BY AN EXPERIMENTAL METHOD

机译：弓形对大海洋航行船舶弹跳/起跳反应的影响

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

Wave induced vibrations often referred to as springing and/or whipping increase the fatigue and extreme loading in ship hull girders. Both effects are disregarded in current ship rules. Various numerical codes exist for predicting the wave induced vibrations, but so far they are not considered reliable. Another means to investigate the importance of the high frequency response, although more resource demanding, is to carry out full scale measurements and/or model tests. Recently, full scale measurements of blunt ships have been carried out by DNV, and in this paper one of these ships was considered and tested in a towing tank to evaluate the additional fatigue damage due to the wave induced vibrations. Different excitation sources may excite the 2-node vertical vibration mode depending on ship design, and it is not straight forward to determine which is more important. The relative importance of the excitation mechanisms are investigated by two approaches in this paper. The first approach separates the whipping from springing to illustrate their relative importance based on basic theory in combination with model test results. The linear and second order transfer functions are utilized in this procedure. The second approach deals with the effect of the bow design on the additional fatigue damage. Three different bows were tested. The first bow design is identical to the real ship. The second bow design is a simplified version of the first one, by removing the bulb and flare. The third bow is fundamentally different from the two former blunt bows. Bow three is sharp pointed with a vertical sharp stem and vertical ship sides. The results indicate that the importance of whipping depends on the sea state, but that it is of similar importance as springing for the sea states that contributes most to the fatigue damage. Moreover, the difference in the additional fatigue damage due to wave induced vibrations for different bow shapes is moderate. This indicates that vessels with pointed bows and without pronounced bow flare, such as LNG vessels, may have a similar contribution from wave induced vibrations. Modern container vessels, which are more slender, but with pronounced bow flares should be further investigated.
机译：波浪引起的振动通常被称为弹跳和/或鞭打，这会增加船体大梁的疲劳度和极限载荷。在当前的船舶规则中都忽略了这两种影响。存在用于预测波浪引起的振动的各种数字代码，但是到目前为止，它们仍不可靠。尽管对资源的需求更多，但研究高频响应重要性的另一种方法是进行满量程测量和/或模型测试。最近，DNV进行了钝船的全尺寸测量，在本文中，对其中一艘进行了考虑，并在拖船中进行了测试，以评估由于波浪引起的振动而造成的额外疲劳损伤。根据船的设计，不同的激励源可能会激发2节点垂直振动模式，因此直接确定哪个更重要并非易事。本文通过两种方法研究了激励机制的相对重要性。第一种方法将鞭打和弹跳分开，以基于基本理论和模型测试结果来说明其相对重要性。在此过程中使用了线性和二阶传递函数。第二种方法处理船首设计对附加疲劳损伤的影响。测试了三种不同的弓箭。第一个船头设计与真实船相同。第二种弓形设计是第一种弓形设计的简化版本，它去除了灯泡和火把。第三把弓与以前的两把钝弓根本不同。船首三是尖锐的，具有垂直的尖茎和垂直的船侧。结果表明，搅打的重要性取决于海况，但其重要性与对疲劳造成最大影响的海态反弹同样重要。而且，对于不同的弓形，由于波浪引起的振动而导致的附加疲劳损伤的差异适中。这表明船首尖而船首没有明显的喇叭口，例如LNG船，可能会由于波浪引起的振动而产生类似的影响。现代的集装箱船比较细长，但船头有明显的喇叭口，应进一步研究。

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