Developing Expression Method of Ship Hull Forms and Improvement of Ship Performance in Waves

船体型式表达方法的发展与船舶波浪性能的改进

• 批准号: 11650946
• 负责人: TAKAKI Mikio
• 金额: $ 2.24万
• 依托单位: HIROSHIMA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11650946/
• 关键词: high-speed slender-body theory; Rankine panel method; transom stern; nonlinear steady disturbance; blunt ship hull form; estimation method in frequency domain; estimation method in time domain; ship hull form parameter; B-spline; 非定常流体力; 非線形自由表面

We have performed the Research Project titled "Developing Expression Method of Ship Hull Forms and Improvement of Ship Performance in Waves" for two years (1999-2000). The main conclusions obtained in this study are summarized as follows :(1) We make clear that the parameters which strongly affected the seakeeping qualities of ship in waves are the vertical prismatic coefficients of the fore and the aft half body and the water plane area coefficient of the fore half body.(2) It is necessary to take into account the lines fairing of a ship hull form to estimate accurately the effect of bow form and the nonlinear steady disturbance. Therefore, we have investigate the method to describe the lines of the ship hull form by using the B-spline function.(3) We have examined the validity of the existing theories estimating the seakeeping qualities of a high-speed vessel. Strip theory is valid for ship speed less than Fn=0.4. High-speed slender-body theory is the most useful method for estimatio … More n of seakeeping qualities of high-speed vessel. The results of Rankine panel method are much improved by dealing with the transom stern as the dry surface. However, it is not enough for accurate estimation of radiation forces.(4) The differences of estimation accuracies due to 3-D estimation theories are small with respect to a fine conventional ship. However, the steady disturbance due to a bow strongly affects the unsteady wave field. Thereby, the Rankine panel method is recommended for estimation of seakeeping qualities because it can easily take into account the effect of steady disturbance.(5) We have developed the estimation method of unsteady forces that takes into account the effect of nonlinear steady disturbance, and have confirmed that it is more accurate method than the existing methods by comparing with the experimental results.(6) The estimation methods in frequency domain are not enough for estimating the nonlinear hydrodynamic forces depending on a time. Therefore, we have tried to develop the estimation method in time domain for developing the excellent ship hull form. At present, we can get the same accurate results as the existing method by using the newly developed method for a fine conventional ship. Less

本研究所在1999-2000年期间实施了“船体形状表示方法的开发与波浪中船舶性能的提高”的研究课题。（1）明确了对船舶在波浪中的耐波性影响最大的参数是前、后半体的垂线棱柱系数和前半体的水线面面积系数。(2)为了准确估计船艏形状和非线性稳态扰动的影响，需要考虑船体线型光顺的影响。因此，本文研究了用B样条函数描述船体线型的方法。(3)我们已经检查了现有的理论估计的耐波性的高速船品质的有效性。当航速小于Fn=0.4时，切片理论是有效的。高速细长体理论是最有用的估算方法。 ...更多信息 高速船耐波性试验研究将方尾作为干面处理，使朗肯面元法的计算结果有了很大的改善。然而，这是不够的辐射力的准确估计。(4)由于3-D估计理论的估计精度的差异相对于优良的常规船舶是小的。然而，由于弓的定常扰动强烈影响非定常波场。因此，推荐用朗肯面元法估算船舶耐波性，因为它能方便地考虑定常扰动的影响。(5)提出了考虑非线性稳态扰动影响的非定常力估算方法，并与实验结果进行了比较，证实了该方法比现有方法更精确。(6)频域估计方法不足以估计依赖于时间的非线性水动力。因此，我们尝试发展时域的估算方法，以发展优良的船体型。目前，将新方法应用于一艘精细常规船，可以得到与现有方法同样精确的结果。少

项目成果

Shiro Kataoka: "Seakeeping Computation of Ships with Forward Speed in Waves by a Time-Domain Green Function Method"Transactions of the West-Japan Society of Naval Architects. No.101 (in print). (2001)

Shiro Kataoka：“通过时域格林函数方法对波浪中前进速度船舶的耐波性计算”西日本造船学会会刊。

Zuogang Chen : "Numerical Investigation on Propulsion by Undulating Plate "日本造船学会論文集. 第88号. 359-366 (2000)

陈作刚：《波动板推进的数值研究》日本造船学会会刊第 88. 359-366 (2000) 号。

Hidetsugu Iwashita: "Prediction of Diffraction Waves of a Blant Ship with Forward Speed Taking account of the Steady Nonlinear Wave Field"Proc. 2nd Numerical Towing Tank Symposium,Rome. 21-2-21-4 (1999)

Hidetsugu Iwashita：“考虑稳定非线性波场，预测前进速度的 Blant 船的衍射波”Proc。

Zuogang Chen: "Numerical Investigation on Propulsion by Undulating Plate"Journal of the Society of Naval Architects of Japan. Vol.88. 359-366 (2000)

陈佐刚：《波动板推进的数值研究》日本造船学会会刊。

Mirel Nechita: "Influence of the Fully Nonlinear Steady Wave Field on the Unsteady Wave Field of a Blunt Ship Advancing in Waves"Transactions of the West-Japan Society of Naval Architects. No.101 (in print). (2001)

Mirel Nechita：“完全非线性稳态波场对波浪中前进的钝船的非稳态波场的影响”西日本造船学会会刊。