3 0 0 0 OA ウォータージェット推進船の曳航能力
- 著者
- 黒田 貴子 大橋 訓英 原口 富博
- 出版者
- 社団法人 日本船舶海洋工学会
- 雑誌
- 日本船舶海洋工学会論文集 (ISSN:18803717)
- 巻号頁・発行日
- vol.18, pp.39-44, 2013 (Released:2014-03-06)
- 参考文献数
- 9
The vessels with waterjet propulsion system increase with the rapid growth in numbers of high speed vessels. It has been increasing when waterjet vessels do towing work. However, the towing performance of waterjet vessels has not been researched clearly.The purpose of this study is to investigate the towing performance of waterjet vessels. Bollard pull test and 2 ways towing tests which are towing ahead and astern were carried out by using the patrol vessels with waterjet of Japan Coast Guard. In general, a standard tow force of propeller vessels is 1.0tf/100PS. However, it was found from the test results that tow force of waterjet vessels is almost half of propeller's one. The cause of drop of towing performance for waterjet is the flow separations at the inlet's lip part.Since the numbers of impeller rotations becomes high to the low ship speed during bollard pull and towing, and the inlet velocity ratio (IVR) which means the inlet velocity to the momentum velocity becomes 1.0 or more. Duct flow of flash type inlet on bollard pull and towing were computed by flow solver "SURF"developed by National Maritime Research Institute. On the basis of those computed results, the loss due to the waterjet duct and the head of propeller and waterjet were evaluated and were compared with the towing test data. Comparison of computed results with test data shows good agreement. The results indicate that towing performance of waterjet can be estimated by evaluating the loss due to the waterjet duct.
1 0 0 0 OA Wave Group中の船体極限挙動に基づく船舶の運航リスク評価手法に関する研究
Wave Groupも含めた任意波中における船舶の挙動を推定するために必要な船体運動時系列計算コードを開発し、模型船を用いた水槽実験結果と比較した。その結果、開発した船体運動計算コードで、定傾斜が付いた状態の運動特性や減揺装置の効果等を精度よく推定できることが確認された。また、開発した船体運動時系列計算コードを用いて、Wave Groupを含む実際の波浪中を航行する船舶の危険性を実用的な観点から評価する手法を検討した。