由於國際油價上漲，節省能源是現在的趨勢，以往漁船會在船艏加裝球狀體，以減少興波阻力，降低耗油量。但是，球型艏通常會有固定設計點，而漁船在出海捕魚時，會因為各種因素導致其船舶姿態變化，偏離原先設計點，導致球型艏的消波效果降低，甚至會造成反效果，故本研究希望設計一種新型船艏(類劍型船艏)來避免上述情況。
本研究以某裝有球狀體之延繩釣漁船為母船，再以盡量不改變船體性能前提下，對其船艏進行改良。接著以CFD軟體(Shipflow)模擬其興波阻力，以及利用ITTC經驗公式求得之摩擦阻力，與母船相互比較，找出各種姿態下最適合的設計船艏。至於如何設計船艏，才能使節能效果更好，由本文系列之結果整理出以下結論：1.將設計吃水處的水線延伸至球型艏之凸出球狀體位置，使球狀體沒有突出艏部(類劍型)2.設計吃水之水線面形狀要避免波浪堆積3.球狀體形狀為倒三角形效果較佳4.球狀體體積越大且越靠近水面效果越好。
又因為漁船於捕魚航程中之各種姿態所佔時間比例不同，故亦時間比重列入考量，得到此次設計中NT5為最適合此趟航程之漁船。其中，由於有改變船體形狀(船艏)，為得知船體於波浪中之運動與附加阻力是否有所變化，故以二維截片理論配合本研究室開發之程式模擬檢視船舶相關之耐海性。

Saving energy has been the worldwide trend due to increasing price of international oil. People usually installed bulb at the bow of fishing vessel in the past for decreasing the wave-making resistance and oil consumption. But, bulbous bow is usually designed at the fixed draft and trim. However, while doing fishing on the sea, the fishing vessel will change the original draft and trim because of various factors which change the sailing attitude. It will reduce the advantage of bulbous bow, and even cause opposite effect. Therefore, aim of this paper is to avoid the above disadvantage by designing a new type bow(Quasi-Sword-Bow).
This article takes a long liner with the bulbous bow at the bow as the original ship. As a prerequisite, to keep the characteristic of ship, and to improve the bow shape of ship. Then, we calculate the wave-making and frictional resistance in different speeds by using Computational Fluid Dynamics (CFD) software and ITTC-1957 formula respectively. To find the most suitable bow shape of ship in different sailing attitude, we compare the above value with the original ship. Finally, according to the data of this paper, we can reach the following way by which we design the bow of ship in order to make the effect of energy-saving better. See the following ways: 1. Extending the waterline of the design draft to the position of bulb which makes the bulb not exceed the bow of ship. 2. The shape of waterline of design draft must be designed to prevent the wave from being accumulated. 3. The better shape of bulb is designed to be inverted triangle shape. 4. The volume of bulb should be bigger and closer to the surface of water.
However, because the proportions of the time of various sailing attitudes are different, we need to take them into consideration. We find that NT5 is the most suitable bow of ship based on an assumed fishing voyage. During the process, we obtained the modified shape of ship, and we also analyze the related ship motion and added resistance by Strip Theory and Potential Theory to investigate the seakeeping characteristics.

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