Second-lrder Changes in Mean Surface Level and Long Period Motious of an Offshore Structure in Shallow Water

浅水中近海结构平均水面的二次变化及长周期运动

• 批准号: 04650398
• 负责人: SAITO Kimio
• 金额: $ 1.34万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04650398/
• 关键词: Shallow Water; Second-order Changes in Mean Surface; Second-order Velocity Potential; Long period Wave Forces; Offshore Structure; Long Period Motions; 2次オーダ速度ポテンシャル

The research on the second-order changes in mean surface level and long period motions of an offshore structs in shallow water have been done during the term of this project and the fellowing reslts have been obtained : 1)The second-order changes in local mean surface level induced by two-dimensional bichromatic radiation waves in an experimental flume with a paddel thpe wave maker have been investigated. From the numerical examples, it has been found that the free-wave vomponent plays an important roll in the evaluation of the local mean surface level. 2)The second-order diffraction problem for a fixed body in bichromatic waves has been solved exactly including the effects of second-order free wanes generated by a wave maker and it has been found that : a)The effects of the second-order velocity potential on the second-order long period wabe forces cannot ve neglected in shallow water. b)The reasonable prediction of second-order long wave forces.

本项目期间对浅水中近海结构物的二阶平均水面变化和长周期运动进行了研究，取得了以下结果：1）在带桨式造波机的实验水槽中，研究了二维双色辐射波引起的局部平均水面的二阶变化。从数值算例中可以看出，自由波分量在估算局地平均海面高度中起着重要的作用。2)本文精确地求解了双色波中固定物体的二阶绕射问题，其中考虑了造波机产生的二阶自由波的影响，并发现：（1）浅水中二阶速度势对二阶长周期波浪力的影响不可忽略。B）二阶长波力的合理预报。

项目成果

Yoshida,H.,Saito,K.: "Second-order Wave Reflection and Transmission by a Fixed Body in Bichromatic Waves on Shallow Water" Proc.of 2nd Symp.on Nonlinear & Free-Surface Flows. 60-63 (1993)

Yoshida,H.,Saito,K.：“浅水中双色波中固定体的二阶波反射和传输”Proc.of 2nd Symp.on Nonlinear

吉田尚史、斎藤公男: "浅水域の構造物に働く長周期波浪強制力について(第一報)" 日本造船学会論文集. 174. 429-437 (1993)

Hisashi Yoshida、Kimio Saito：“作用于浅水结构的长周期波浪力（第一份报告）”日本造船学会汇刊 174. 429-437 (1993)。

Yoshida,H.,Saito,K.: "Irregularities in the Solution at the Intersection of the Free Surface for Radiation Problem of a Floating Body" Proc.Korea-Japan Workshop on Hydrodynamic in Ship Design. 249-251 (1993)

Yoshida,H.,Saito,K.：“浮体辐射问题自由表面交叉点解中的不规则性”Proc.Korea-Japan Workshop on Hydrodynamic in Ship Design。

tishida, H., Saito, K.: "Second-order Wave reflection and Transmission by a Fixed Body in Bichromatic Waces on Shallow Water" Proc. of 2nd Symp. on Nonlinear & Free-Surface Flows. 60-63 (1993)

tishida, H., Saito, K.：“浅水中双色波中固定体的二阶波反射和传输”Proc。

Yoshida,H.and Saito,K.: "Irregularities in the Solution at the Intersection of the Free Surface for Radiation Problem of a Floating Body" Proc.Korea-Japan Workshop on Hydrodynamic in Ship Design. 249-251 (1993)

Yoshida,H. 和 Saito,K.：“浮体辐射问题自由表面交叉点解中的不规则性”Proc.Korea-Japan Workshop on Hydrodynamic in Ship Design。