操船導引系統應用於風浪中大型貨櫃船航行之研究

Investigation on the Operator Guidance System for a Large Container Ship Travelling in Rough Seas

本文針對國內較罕見之大型貨櫃船實船航程中耐海性能量測進行分析，量測實船為一艘4,950TEU級大型貨櫃船，所得之實船量測結果並與二維勢流理論計算結果比較。實船量測地點跨越北太平洋海域（美國西岸至韓國），整個航程約11天，實船量測紀錄達66次，其中包括全船運動性能量測10次（2個速度、5個航向角）。經由船舶在實際海況中的橫搖、縱搖運動量測資料與運動性能程式（USDDCMO）計算結果比較顯示；使用二維勢流理論針對本船在非規則波浪中之橫搖運動反應的計算，除頂浪航況外，理論計算值與量測值差異不大，但本船在波浪中之橫搖運動反應於舵浪航況時最為劇烈，且船速愈高，橫搖運動反應愈大。對於縱搖運動性能預估方面，雖顯示出理論計算值略為低估，然其定性上的趨勢一致，即最大縱搖運動反應發生在頂浪航況，縱搖運動反應亦隨著船速之增加而增大。本研究並依實船量測比較結果配合修正數值計算模式，據以製成操船資訊導引系統界面，提供航海人員於實際風浪中操船之參考；其可預估大型貨櫃船在風浪中之運動反應，並依不同船舶裝載狀況、船速、波浪海況及運動反應等限制條件，自動搜尋最適風浪中操船方位及航速，可有效降低大型貨櫃船在風浪中之劇烈縱搖及橫搖運動反應，避免大型貨櫃船之貨物傾倒或翻覆，造成船舶航行危險；此外，本文亦對於大型貨櫃船在頂浪風浪中經常發生之參數橫搖（Parametric rolling）現象，經由實船量測訊號分析，進行討論。 The primary work of this project is to investigate the seakeeping performance of a 4,950 TEU container ship traveling in waves, and to develop the operator guidance system for providing the useful information for crew sailing in rough seas. In this study, the sea trials of seakeeping are carried out with a 4,950 TEU container ship. There are over 66 sea trial records, which include motion tests with varied speeds and headings, have been completed in this project. The measuring area covers the seas around North Pacific Ocean from USA to Korea. Numerical results of seakeeping performance have been carried out by the two-dimensional potential theory for a 4,950 TEU container ship and validated by the data obtained from sea trials. The comparison between numerical predictions and sea trial data shows a good agreement except the one around the head sea condition of roll motion. An operator guidance system has been developed by using the validated seakeeping performance database and incorporated with a friendly information interface. It can provide the optimum speed and heading for crews in order to reduce the motion responses of large container ships in rough weather. Finally, the phenomena of parametric rolling of large container ship in head sea have been discussed by through the sea trial signals.