船舶與海洋工程畢業(yè)設(shè)計外文翻譯

1、<p>　　A Simple Prediction Formula of Roll Damping of Conventional Cargo Ships on the Basis of lkeda's Method and Its Limitation</p><p>　　Yuki Kawahara, Kazuya Maekawa and Yoshiho Ikeda</p>&l

2、t;p>　　Department of Marine System Engineering, Osaka Prefecture University, Sakai 599-8531’ Japan</p><p>　　??????????Since the roll damping of ships has significant effects of viscosity, it is difficult t

3、o calculate it theoretically. Therefore, experimental results or some prediction methods are used to get the roll damping in design stage of ships. Among some prediction methods, Ikeda’s one is widely used in many ship m

4、otion computer programs. Using the method, the roll damping of various ship hulls with various bilge keels can be calculated to investigate its characteristics. To calculate the roil </p><p>　　Key words: Rol

5、l damping, simple prediction formula, wave component, eddy component, bilge keel component.</p><p>　　Introduction</p><p>　　In 1970s, strip methods for predicting ship motions in 5-degree of free

6、doms in waves have been established. The methods are based on potential flow theories (Ursell-Tasai method, source distribution method and so on), and can predict pitch, heave, sway and yaw motions of ships in waves in f

7、airly good accuracy. In roll motion, however, the strip methods do not work well because of significant viscous effects on the roll damping. Therefore, some empirical formulas or experimental data are used to </p>

8、<p>　　To improve the prediction of roll motions by these strip methods, one of the authors carried out a research project to develop a roll damping prediction method which has the same concept and the same order of

9、 accuracy as the strip methods which are based on hydrodynamic forces acting on strips. The review of the prediction method was made by Himeno [5] and Ikeda [6，7] with the computer program.</p><p>　　The pred

10、iction method, which is now called Ikeda’s method, divides the roll damping into the frictional (BF), the wave (Bw)，the eddy (Be) and the bilge keel (Bbk) components at zero forward speed, and at forward speed, the lift

11、(Bi) is added. Increases of wave and friction components due to advance speed are also corrected on the basis of experimental results. Then the roll damping coefficient B44 (= roll damping moment (kgfm)/roll angular velo

12、city (rad/sec)) can be expressed as follows:</p><p>　　B44Bbk (1)</p><p>　　At zero forward speed, each component except the friction and lift components are predicted for each cross section with

13、 unit length and the predicted values are summed up along the ship length. The friction component is predicted by Kato’s formula for a three-dimensional ship shape. Modification functions for predicting the forward speed

14、 effects on the roll damping components are developed for the friction, wave and eddy components. The computer program of the method was published, and the metho</p><p>　　For these 30 years, the original Ike

15、da’s method developed for conventional cargo ships has been improved to apply many kinds of ships, for examples, more slender and round ships, fishing boats, barges, ships with skegs and so on. The original method is als

16、o widely used. However, sometimes, different conclusions of roll motions were derived even though the same Ikeda’s method was used in the calculations. Then, to check the accuracy of the computer programs of the same Ike

17、da’s method, a more simp</p><p>　　Previous Prediction Formula</p><p>　　The simple prediction formula proposed in previous paper can not be used for modem ships that have high position of center

18、of gravity or long natural roll period such as large passenger ships with relatively flat hull shape. In order to investigate its limitation, the authors compared the result of this prediction method with original Ikeda’

19、s one while out of its calculating limitation. Fig. 1 shows the result of the comparison with their method of roll damping. The upper one is on the condition</p><p>　　From this figure, the roll damping estim

20、ated by this prediction formula is in good agreement with the roll damping calculated by the Ikeda’s method for low position of center of gravity, but the error margin grows for the high position of center of gravity. Th

21、e results suggest that the previous prediction formula is necessary to be revised.</p><p>　　Methodical Series Ships</p><p>　　Modified prediction formula will be developed on the basis of the pre

22、dicted results by Ikeda’s method using the methodical series ships. This series ships are constructed based on the Taylor Standard Series and its hull shapes are methodically changed by changing length, beam, draft, mids

23、hip sectional coefficient and longitudinal prismatic coefficient. The geometries of the series ships are given by the following equations.</p><p>　　Proposal of New Prediction Method of Roll Damping</p>

24、<p>　　In this chapter, the characteristics of each component of the roll damping, the frictional, the wave, the eddy and the bilge keel components at zero advanced speed, are discussed, and a simple prediction for

25、mula of each component is developed.As well known, the wave component of the roll damping for a two-dimensional cross section can be calculated by potential flow theories in fairly good accuracy. In Ikeda's method, t

26、he wave damping of a strip section is not calculated and the calculated value</p><p>　　Conclusions</p><p>　　A simple prediction method of the roll damping of ships is developed on the basis of t

27、he Ikeda’s original prediction method which was developed in the same concept as a strip method for calculating ship motions in waves. Using the data of a ship, B/d, Cb，Cm, OG/d, G)，bBK/B, Ibk/Lpp，(pa, the roll damping o

28、f a ship can be approximately predicted. Moreover, the limit of application of Ikeda’s prediction method to modern ships that have buttock flow stern is demonstrated by the model experiment. The</p><p>　　Thi

29、s work was supported by the Grant-in Aid for Scientific Research of the Japan Society for Promotion of Science (No. 18360415).</p><p>　　The authors wish to express sincere appreciation to Prof. N. Umeda of O

30、saka University for valuable suggestions to this study.</p><p>　　References</p><p>　　Y. Ikeda, Y. Himeno, N. Tanaka, On roll damping force of shipEffects of friction of hull and normal force of

31、bilge keels, Journal of the Kansai Society of Naval Architects 161 (1976) 41-49. (in Japanese)</p><p>　　Y. Ikeda, K. Komatsu, Y. Himeno, N. Tanaka, On roll damping force of ship~Effects of hull surface press

32、ure created by bilge keels, Journal of the Kansai Society of Naval Architects 165 (1977) 31-40. (in Japanese)</p><p>　　Y. Ikeda, Y. Himeno, N. Tanaka, On eddy making component of roll damping force on naked

33、hull, Journal of the Society of Naval Architects 142 (1977) 59-69. (in Japanese)</p><p>　　Y. Ikeda, Y. Himeno, N. Tanaka, Components of roll damping of ship at forward speed, Journal of the Society of Naval

34、Architects 143 (1978) 121-133. (in Japanese)</p><p>　　Y. Himeno, Prediction of Ship Roll Damping一State of the Art, Report of Department of Naval Architecture & Marine Engineering, University of Michigan,

35、 No. 239, 1981.</p><p>　　Y. Ikeda, Prediction Method of Roll Damping, Report of Department of Naval Architecture, University of Osaka Prefecture, 1982.</p><p>　　Y. Ikeda, Roll damping,in: Proce

36、edings of 1st</p><p>　　Symposium of Marine Dynamics Research Group, Japan, 1984, pp. 241-250. (in Japanese)</p><p>　　Y. Kawahara, Characteristics of roll damping of various ship types and a simp

37、le prediction formula of roll damping on the basis of Ikeda’s method, in: Proceedings of the 4th Asia-Pacific Workshop on Marine Hydrodymics, Taipei, China, 2008，pp. 79-86.</p><p>　　Y. Ikeda, T. Fujiwara, Y.

38、 Himeno, N. Tanaka, Velocity field around ship hull in roll motion, Journal of the Kansai Society of Naval Architects 171 (1978) 33-45. (in Japanese)</p><p>　　N. Tanaka, Y. Himeno,Y. Ikeda, K. Isomura,</

39、p><p>　　Experimental study on bilgekeel effect for shallow draft</p><p>　　ship, Journal of the Kansai Society of Naval Architects 180 (1981) 69-75. (in Japanese)</p><p>　　常規(guī)貨船的橫搖阻尼在池田

40、方法基礎(chǔ)上的一個簡單預(yù)測方法及其局限性</p><p>　　Yuki Kawahara, Kazuya Maekawa and Yoshiho Ikeda</p><p>　　海洋系統(tǒng)工程部，酒井599-8531日本大阪府立大學</p><p>　　摘要：由于船的橫搖阻尼對其粘度有顯著的影響，所以很難在理論上計算。因此，某些實驗結(jié)果或某些預(yù)測方法都被用于一般的設(shè)計階

41、段。在這些預(yù)測方法中，池田方法被廣泛應(yīng)用于許多船舶運動的計算機程序。使用這個方法，可以對含有各種舭龍骨的船體進行計算，從而探討其不同的特性。為了計算每個船的橫搖阻尼，詳細的數(shù)據(jù)也是必須的。因此，在設(shè)計初期就需要更為簡便的預(yù)測方法。方法雖然簡單，但也得通過電腦程序的驗證并證明在池田方法的基礎(chǔ)上是有用的。在這個基礎(chǔ)上推導出的簡便公式就是現(xiàn)在的這個在本文件。船體形式的變化是通過改變船長，船寬，吃水，中橫剖面系數(shù)及棱形系數(shù)來等來等到。然而這個簡

42、化公式不能用于具有較高的重心位置的船。所以，一些改進的方法以提高準確行就應(yīng)運而生了。</p><p>　　關(guān)鍵詞：橫搖阻尼，簡單的預(yù)測公式，波分量，渦分量，舭龍骨組件。</p><p><b>　　介紹</b></p><p>　　在20世紀70年代以來，船舶在波浪中的運動已發(fā)展成了具有5個自由度的運動形式，新的預(yù)測方法已經(jīng)建立。該方法是基于勢

43、流理論（Ursell-Tasai 方法，源分布法等），可以預(yù)測間距，升沉，搖擺及波浪中船的偏航運動，并都有不錯的精度。然而在橫搖運動中，帶條的方法并適合。因為粘性效應(yīng)對對橫搖阻尼有很大的影響。所以，就需要用一些經(jīng)驗公式和實驗數(shù)據(jù)來檢驗這些公式。</p><p>　　為了提高這些帶鋼方法預(yù)測橫搖運動的準確性，作者之一就就開發(fā)了一些項目來發(fā)展這個橫搖預(yù)測方法，而這些都是基于水動力帶條方法，都有相似的概念和順序，精確度

44、也能夠保證。預(yù)測方法是由姬野[5]和池田[6,7]的計算機程序?qū)彶椤?lt;/p><p>　　預(yù)測的方式，現(xiàn)在叫池田方法，被分為了零航速阻尼的摩擦（BF），波浪（BW），渦流（BE）和舭龍骨（BBK）組件，前進的速度，升降機（Bi）。在校正實驗結(jié)果的基礎(chǔ)上，推進速度的波和摩擦部件增加。</p><p>　　前進速度為零，各組成部分之外的摩擦和電梯部件的每個橫截面，單位長度預(yù)測，預(yù)測值總結(jié)了沿船

45、的長度。摩擦成分預(yù)測由加藤的公式為一個三維的船舶形狀。預(yù)測橫搖阻尼元件的前進速度的影響的修改功能的開發(fā)的摩擦，波浪和渦流組件。這個方法的計算機程序也已經(jīng)開發(fā)出來了，并被廣泛的使用。</p><p>　　30年間，原始池田方法開發(fā)傳統(tǒng)船舶已被該進，以適用于多種船舶，例如：更加修長和方形的船舶，漁船，駁船，帶有尾鰭的船等等。原來的方法也被廣泛使用。但是，有時，橫搖運動的不同的結(jié)論，即使來自相同池田的方法，在計算中使用

46、。然后，判斷是否相同池田的方法，與幾乎相同的精度池田原來一直期望開發(fā)一種更簡單的預(yù)測方法的計算機程序的準確性。有人說，在船舶設(shè)計階段，池田的方法太復(fù)雜，使用。為了滿足這些需求，使用回歸分析，推導出一個簡單的橫搖阻尼預(yù)測方法。</p><p><b>　　以前的預(yù)測公式</b></p><p>　　前文中提出的簡單的預(yù)測公式不能用于的調(diào)制解調(diào)器船舶有高重力或自然卷長期間

47、，如大型客船船體形狀相對平坦的中心位置。為了研究它的局限性，作者比較的結(jié)果，這種預(yù)測方法與原池田之一，而其計算限制。實驗結(jié)果與他們的方法的橫搖阻尼。最上層在重心低的情況下，下面那層是在低重心的情況下。</p><p>　　從這個數(shù)字看，這個公式估計的結(jié)果與池田公式對低重心船的估計結(jié)果很好的吻合，對高重心船會有誤差。實驗結(jié)果表明，以前的預(yù)測公式需要被修改。、</p><p><b>

48、;　　成型的系列船</b></p><p>　　修改的的公式可以用成型的系列船型來發(fā)展成為池田公式的預(yù)測結(jié)果。該系列的船是在泰勒船型的基礎(chǔ)上建立的，通過對他的船長，船寬，吃水，中橫剖面系數(shù)及縱向棱形系數(shù)來實現(xiàn)。</p><p>　　減搖預(yù)報的新方法建議</p><p>　　本章中，每個組件的一些特性，如橫搖阻尼，摩擦，波浪力，渦流和舭龍骨組件，都是在靜水

49、中討論并得出的簡化公式。眾所周知，二維橫截面的波分量可以通過勢流理論精確的計算。在池田的方法中，條狀橫截面的興波阻尼不能計算得到，而通過勢流理論得到的計算值曾經(jīng)一直被使用，因為粘性效應(yīng)值在橫搖阻尼有如此的重要性。</p><p><b>　　結(jié)論</b></p><p>　　在池田原預(yù)測方法的基礎(chǔ)上，這是相同概念作為一個條法計算船舶運動波的方式，并用船舶橫搖阻尼開發(fā)的

50、一個簡單預(yù)測方法。用到的數(shù)據(jù)，B/d, Cb，Cm, OG/d, G)，bBK/B, Ibk/Lpp 。此外，模型實驗證明了池田的預(yù)測方法，特別是在現(xiàn)代船舶的用途上，但有一定的限制。</p><p>　　The limit of Large Vessels</p><p>　　on Feb 21st, the industry was shocked by the news that AP

51、 Moller-Maersk placed an order of 10 container ships of 18,000 TEU with the South Korean ship yards. The order brings the development of large vessels to a new climax and at the same time puts forward a series of researc

52、h subjects to the industry, such as what is the limit for the development of large vessels, whether ship safety can be guaranteed, and etc.</p><p>　　In relation to the current development trend of large vess

53、els, the chief engineer of Jiangnan Shipbuilding (Group) Company Ltd. Mr. Hu Keyi believes that from the perspective of theory and technology, there is no problem with the development of large vessels, even with the deve

54、lopment of “infinitely large vessels”，however, the size of ships is limited by many factors such as channels, ports, wharf depth and the ability of cargo collection of shipowners. Therefore, such "infinite largeness

55、" is re</p><p>　　In every period of time, the development of large vessels faces many constraints. However, as seen from the history of development (in particular container ships), each limit value"

56、; predicted by experts has been broken one by one. This gives an enlightenment to the industry: on one hand, development of large vessels can not ignore the constraints of practical conditions, on the other hand, it can

57、not be restricted by the practical conditions. In today when science and technology are developing a</p><p>　　At present, the industry pays close attention to the development of large vessels and at the same

58、 time the safety of ships.</p><p>　　Chen Yongnian from R&D center of CCS thinks that, though there are the preconditions in terms of theory and technology for the development of large vessels, the issue

59、of safety cannot be underestimated. Since the accidents involving these “Big Macs” will be devastating.</p><p>　　In traditional theory，the ability of withstanding waves will get stronger with the increase of

60、 the size of ships. However, we should be fully aware that human beings haven’t fully grasped the factors which affect vessels， strength and safety, in particular, the history of the development of large vessels is not l

61、ong, and data accumulated is relatively limited, the safety of large vessels hasn't been verified in many aspects and there are still a lot of unknown factors affecting the safety of shi</p><p><b>

62、　　大型船舶的限制</b></p><p>　　2月21日，被業(yè)界震驚的消息，AP穆勒 - 馬士基集團下訂單的10與韓國造船廠18,000 TEU集裝箱船。該訂單使大型船舶發(fā)展到了一個新的高潮，并在同一時間提出了一系列研究對象，如發(fā)展大型船舶的極限是什么，是否可以保證船舶安全等。 就目前的發(fā)展趨勢，大型船舶，江南造船（集團）公司總工程師有限公司胡先生科藝認為，從理論和技術(shù)的角度來看，大型船舶的

63、發(fā)展是沒有問題的，即使有問題，發(fā)展船舶的大小是由許多因素決定，如通道，港口，碼頭的深度和船東攬貨能力。因此，這種“無限大”是相對的。</p><p>　　在每一段時間中，大型船舶的發(fā)展面臨著許多制約因素。然而，從歷史的發(fā)展（尤其是集裝箱船），每個限值“專家預(yù)測已被一個接一個打破，這給出了一個行業(yè)的啟示：一方面，大型船舶的發(fā)展不能忽視現(xiàn)實條件的制約，另一方面，它不能被限制的實際情況，在今天，在科學技術(shù)發(fā)展速度快，沒

64、有什么是不可能的。AP穆勒 - 馬士基集團和韓國船廠的優(yōu)異性能集裝箱船在該地區(qū)是一個很好的例子，這是值得更多的關(guān)注和研究，從中國的港口業(yè)，造船業(yè)，航運業(yè)及相關(guān)行業(yè)。 目前，業(yè)界密切關(guān)注大型船舶的發(fā)展，同時船舶的安全。</p><p>　　陳擁輦CCS研發(fā)中心認為，雖然有方面的理論和技術(shù)的發(fā)展，大型船舶的先決條件，安全問題不能被低估。由于事故涉及這些“巨無霸”將是毀滅性的。</p><

65、p>　　在傳統(tǒng)理論中，與一般的大小的增加，承受波浪的能力將得到更強。但是，我們應(yīng)該充分認識到，人類還沒有完全掌握船只，強度和安全性因素影響，尤其是大型船舶的發(fā)展，歷史不長，積累的數(shù)據(jù)是相對有限的，安全的大型船舶被證實在許多方面仍存在很多未知因素，影響船舶安全。因此，在大型船舶的發(fā)展，這將是不可避免的，有一些安全問題。在日本核電站事故一樣，當他們第一次建的工廠，他們沒有預(yù)測，這樣的事故可能發(fā)生在未來。他們只能使他們認為是最好的解決方