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Development of a Wave-Damping Stern for a Container Ship
No full text本研究主要著眼於船艉幾何形狀，就降低阻力為目標之優化設
計。本研究針對台灣國際造船公司所提供之CV1700 貨櫃船之
RD542_0船型，利用電腦輔助設計與參數化設計之方法進行船型變化
規劃，再使用計算流體力學方法進行流場之計算，計算過程採有限體
積法與結構化網格離散計算空間，以計算穩態具船舶周圍自由液面黏
性流場。在計算不同船艉幾何形狀流場前，先針對原型船進行流場計
算，因該貨櫃輪已有漢堡實驗水槽之實驗資料，藉由與實驗資料比對
來驗證。在所使用網格密度分別為一百萬點、兩百萬點與四百萬點
時，其與實驗值比對之誤差分別為-4.79%、-4.81%與-0.88%，計算結
果與實驗之誤差相當均在5%以內。而流場之局部物理性質（如流場
速度分佈、水面波形）和實驗值也相當接近。
接著進行不同船艉幾何形狀之流場計算，計算條件為裸船殼，漢
堡船模尺寸(縮尺比23.76)，弗勞德數(Froud Number)為0.25(相當於實
船船速20.1節)，姿勢為平浮。由本研究計算與台大水槽實驗結果，證
實新船型之規劃，在特定之吃水狀況下，有助於壓制船艉部之興波，
達成總阻力減低之成效。另外為了研究艉部船形系統化改變對於艉部
流場產生壓浪之效果，利用艉部幾何相關之參數艉框架縱向斜角與橫
剖面特性(呈S形狀之程度)與船艉鴨形艉延伸之長度產生了一系列之
2
船形，以作為貨櫃船艉部船形幾何設計參數化研究之基礎。In this research, we primarily focus on an optimal design of a
wave-damping stern for a container ship .To generate a basis for
designing a new stern form or to improve the hull form, a series of stern
by a parametric-design method is conducted on a container ship provided
by a shipyard . Simultaneously , a CFD method is introduced to predict
the ship resistance . The applized CFD method is validated by comparing
with HSVA experimental results with numerical prediction .The margin
of error is less then 5% for grids with 1 million cells grid .As the number
of cell increases to 4 million , the margin of error further reduces to
smaller than 1%.
Both numerical prediction and experimental result obtain on the
NTU towing tank indicate that the new stern form is better than the basic
form by reducing the crest of stern wave.
Besides , this research creates a series of hull forms by varing with
stern frame angle longitudinally, crosswise with cross-section properties
and the elongation of ducktail which are for the sake of researching on
the wave-damping effect of the new stern shape.第1 章 緒論..........................................................................................................4
第2 章 船型之規劃與繪製..............................................................................7
2.1. 船形變化規劃之構想................................................................................7
2.2. 線型繪製..................................................................................................11
2.3. 橫向剖面形狀(NPT1~NPT4)..................................................................14
2.4. 縱向艉框架之角度................................................................................15
第3 章 CFD數值方法與驗證........................................................................20
3.1. 統御方程式..............................................................................................20
3.2. 紊流模型..................................................................................................20
3.3. 數值方法..................................................................................................21
3.4. 船殼所受合力之計算..............................................................................22
3.5. 自由液面計算..........................................................................................22
3.6. 平行計算..................................................................................................24
3.7. 網格測試..................................................................................................24
3.8. 數值方法測試..........................................................................................28
3.9. 計算條件..................................................................................................30
3.10. 原型船計算之驗證..............................................................................31
3.9.1 不同尺寸之船模計算..................................................................31
3.9.2 考慮下沉量之流場計算..............................................................31
第4 章 台灣國際造船設計船型之計算.....................................................36
4.1 PT-1 與PT-2 .............................................................................................36
4.2 方形艉傾斜角度之影響..........................................................................36
4.3 設計吃水(8.5m)下之NPT-104 與RD5421A0.........................................38
4.4 實際吃水(8.9m)下之NPT-104 與RD5421A0.........................................40
4.5 實際吃水(8.9m)下之RD542_1、RD5421A0 與RD542_0 ....................42
4.6 台灣國際造船船型之CFD與實驗比對..................................................44
第5 章 新船型之計算......................................................................................48
5.1. 8.9 米吃水之計算....................................................................................48
5.2. 9.49 米吃水之計算..................................................................................54
5.2.1. RD542_0、RD542_1、NPT-104......................................................54
5.2.2. NPT-1 系列........................................................................................59
5.2.3. NPT-2 系列........................................................................................60
5.2.4. NPT-3 系列........................................................................................61
5.3. 8.36 米吃水之計算..................................................................................63
5.3.1. NPT-1 系列........................................................................................66
5.3.2. NPT-2 系列........................................................................................67
II
5.3.3. NPT-3 系列........................................................................................67
5.3.4. WDA船型..........................................................................................68
5.4. 小結..........................................................................................................71
第6 章 鴨形艉延伸長度.................................................................................73
5.1. 8.9 米吃水之計算....................................................................................73
6.1.1. NPTX-4 系列.....................................................................................74
6.1.2. RD542_1 系列...................................................................................76
6.1.3. RD542_0 系列...................................................................................78
5.2. 8.633 米吃水之計算................................................................................82
6.2.1. NPTX-4 系列.....................................................................................82
6.2.2. RD542_1 系列...................................................................................84
5.3. 9.49 米吃水之計算..................................................................................87
6.3.1. RD542_1 系列...................................................................................87
第7 章 結論與建議..........................................................................................90
7.1. 結論..........................................................................................................90
7.2. 建議與未來方向......................................................................................92
附表............................................................................................................................95
附圖..........................................................................................................................11
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koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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