受到非高斯波负荷的杰克平台的动态放大
1Department of Ocean Engineering, Technical University of Denmark, Building 101 E, DK-2800 Lyngby, Denmark.
概括
起重机平台中的动态放大受非线性波负荷的影响. 对非正常激发的扩散理论预测与时间模拟进行了比较,显示差异主要是由于抑制假设.
科学领域:
- 海洋工程 海洋工程
- 结构动力学 结构动力学
- 波浪力学 波浪力学
背景情况:
- 升级平台由于其长的自然周期 (7-8s) 而表现出显著的动态放大.
- 这些平台上的波刺激力与波高度非线性,导致非正常分布的随机负荷.
- 线性理论足够地描述了平台运动,但并没有描述激发特性.
研究的目的:
- 为了比较从扩散理论 (扩展到非正常激发) 的动态放大预测,与不规则的海路中的杰克-up平台的时间模拟结果.
- 为了调查理论预测和模拟结果之间的差异,关于波高的非线性反应.
- 确定影响动态放大预测准确性的因素.
主要方法:
- 利用扩散理论,适应非正常的激发条件.
- 在不规则的海路中执行平台响应的时间模拟.
- 通过两种方法获得的动态放大因子和响应特征进行了比较.
- 分析了总阻尼对观察到的差异的影响.
主要成果:
- 与扩散理论预测相比,时间模拟通常表明波高度响应的非线性较少.
- 在这两种方法之间的动态放大估计中观察到差异.
- 选择全缓方式显著影响了扩散理论预测的准确性.
结论:
- 扩散理论,即使扩展到非正常激发,也可能低估了在不规则波中杰克-上平台反应的非线性.
- 精确模拟总缓对于提高扩散理论在预测动态放大中的可靠性至关重要.
- 需要进一步的研究来完善理论模型,以更好地匹配复杂的海上结构的模拟结果.
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