Development of a Software for Predicting Propulsion Performance of Ships in Waves

本研究旨在开发一种预测船舶在波浪中的推进性能的软件。将Rankine面板法推广到考虑定常波场的船舶在波浪中的非定常问题，该方法已被用于平流中推进性能的预测。前两年主要进行了以下研究：(1)发展了定常问题的Rankine面板法，可求解完全非线性的定常自由面问题；(2)发展了非定常问题的Rankine面板法，可将完全非线性的定常波场考虑到非定常问题中；(3)进行了细长和钝型船舶的计算，并与实验结果进行了比较。(4)将方法扩展到适用于低频范围。在最后一年，我们通过简单的数值模拟明确了拖曳槽的侧壁效应，并验证了(4)实验中得到的非定常波型。此外，我们将大量的实验数据重新整理，作为可供其他研究人员使用的数据库，并使软件界面丰富，方便其他用户使用。

This study aimed to develop a software to predict propulsion performance of ships in waves. The Rankine panel method, which has been used for predicting propulsion performance in carm water, extended to the unsteady problem of ships in waves taking into account of the steady wave field. The following researches were carried out in the first two years : (1) Development of the Rankine panel method for the steady problem, which can solve the fully nonlinear steady free-surface problem, (2) Development of the Rankine panel method for the unsteady problem, which can take into account of the fully nonlinear steady wave field into the unsteady problem, (3) Computations for slender and blunt ships and comparison of numerical results with experiments which were also carried out through this study, (4) Extension of the method to be applicable to the low frequency range. In the final year we made clear the side wall effects of a towing tank by a simple numerical simulation and validated the unsteady wave patterns experimentally obtained in (4). Additionally we rearranged plenty of experimental data as a data-base which can be utilized by another researchers, and the interface of the software is made replete for the convenience of another users.