An Efficient Numerical Method for Higher Order Springing Induced Loads

高阶弹振诱发载荷的有效数值方法

• 批准号: 311018823
• 负责人: Professor Dr.-Ing. Bettar Ould El Moctar
• 金额: --
• 依托单位: Institut für Schiffstechnik, Meerestechnik und Transportsysteme (ISMT)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/311018823?language=en
• 关键词: Efficient; Numerical; Method; Higher; Order

The aim of this project is to further develop a three dimensional boundary element method based on Rankine sources to predict sectional loads acting on ship structures in waves taking into account springing induced hydroelasticity effects. Wave induced forces leading to resonant ship responses are subdivided into Froude-Krylov, radiation and diffraction forces. For higher order springing it is important to consider nonlinear effects related to Froude-Krylov forces. These forces are computed in each time step based on the instantaneous wetted surface. With regard to springing diffraction and radiation forces can be treated in a linear way. They are computed in the frequency domain and transferred in the time domain using convolution integrals. To account for hydroelasticity effects the flow equations are coupled with the equations of motion (rigid and elastic). The elastic deformations are computed using a modal decomposition approach to efficiently solve a reduced set of natural modes. A Vlasov beam and three dimensional Finite-Element models will be used. Further, simplified methods for prediction of hydrodynamic damping will be developed and verified. The methods to be developed are extensively validated using results from model tests and field methods based on Reynolds-Averaged-Navier-Stokes-Equations.

该项目的目的是进一步开发一种基于朗肯源的三维边界元方法，以预测波浪中作用在船舶结构上的截面载荷，同时考虑弹跳引起的水弹性效应。导致船舶共振响应的波浪力被细分为弗劳德-克雷洛夫力、辐射力和衍射力。 对于高阶弹跳，重要的是要考虑与 Froude-Krylov 力相关的非线性效应。这些力是根据瞬时润湿表面在每个时间步长中计算的。关于弹跳衍射和辐射力可以以线性方式处理。它们在频域中计算并使用卷积积分在时域中传输。为了考虑水弹性效应，流动方程与运动方程（刚性和弹性）耦合。 使用模态分解方法计算弹性变形，以有效地求解一组简化的自然模态。将使用 Vlasov 梁和三维有限元模型。此外，还将开发和验证用于预测流体动力阻尼的简化方法。使用基于雷诺平均纳维斯托克斯方程的模型测试和现场方法的结果对要开发的方法进行了广泛的验证。

项目成果

A time domain boundary element method for wave added resistance of ships taking into account viscous effects

考虑粘性效应的船舶波浪增阻时域边界元法

• DOI: 10.1016/j.oceaneng.2018.05.010
• 发表时间: 2018-08-01
• 期刊: Ocean Engineering
• 影响因子: 5
• 作者: M. Riesner;O. E. Moctar
• 通讯作者: O. E. Moctar

Prediction of non-linear ship responses in waves considering forward speed effects

考虑前进速度影响的非线性船舶波浪响应预测

• DOI: 10.1080/09377255.2016.1221607
• 发表时间: 2016
• 期刊: Ship Technology Research
• 影响因子: 2.2
• 作者: Riesner; M.; von Graefe; A.; Shigunov; V.; el Moctar; O.
• 通讯作者: O.

Rankine source time domain method for nonlinear ship motions in steep oblique waves

陡斜波中船舶非线性运动的朗肯源时域法

• DOI: 10.1080/17445302.2018.1498568
• 发表时间: 2018
• 期刊: Ships and Offshore Structures
• 影响因子: 2.1
• 作者: Riesner; M.; Chillcce; G.; el Moctar; O.
• 通讯作者: O.