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重 慶 理 工 大 學(xué)
文 獻(xiàn) 翻 譯
二級學(xué)院 重慶理工大學(xué)機(jī)械工程學(xué)院
班 級 109040205
學(xué)生姓名 林洋 學(xué) 號 10904020511
譯 文 要 求
1、譯文內(nèi)容必須與課題(或?qū)I(yè))內(nèi)容相關(guān),并需注明詳細(xì)出處。
2、外文翻譯譯文不少于2000字;外文參考資料閱讀量至少3篇(相當(dāng)于10萬外文字符以上)。
3、譯文原文(或復(fù)印件)應(yīng)附在譯文后備查。
譯 文 評 閱
導(dǎo)師評語(應(yīng)根據(jù)學(xué)?!白g文要求”,對學(xué)生外文翻譯的準(zhǔn)確性、翻譯數(shù)量以及譯文的文字表述情況等作具體的評價(jià))
指導(dǎo)教師:
年 月 日
1
機(jī)械設(shè)計(jì)是一門通過設(shè)計(jì)新產(chǎn)品或者改進(jìn)老產(chǎn)品來滿足人類需求的應(yīng)用技術(shù)科學(xué)。它涉及工程技術(shù)的各個(gè)領(lǐng)域,主要研究產(chǎn)品的尺寸、形狀和詳細(xì)結(jié)構(gòu)的基本構(gòu)思,還要研究產(chǎn)品在制造、銷售和使用等方面的問題。
進(jìn)行各種機(jī)械設(shè)計(jì)工作的人員通常被稱為設(shè)計(jì)人員或者機(jī)械設(shè)計(jì)工程師。機(jī)械設(shè)計(jì)是一項(xiàng)創(chuàng)造性的工作。設(shè)計(jì)工程師不僅在工作上要有創(chuàng)造性,還必須在機(jī)械制圖、運(yùn)動學(xué)、工程材料、材料力學(xué)和機(jī)械制造工藝學(xué)等方面具有深厚的基礎(chǔ)知識。
如前所訴,機(jī)械設(shè)計(jì)的目的是生產(chǎn)能夠滿足人類需求的產(chǎn)品。發(fā)明、發(fā)現(xiàn)和科技知識本身并不一定能給人類帶來好處,只有當(dāng)它們被應(yīng)用在產(chǎn)品上才能產(chǎn)生效益。因而,應(yīng)該認(rèn)識到在一個(gè)特定的產(chǎn)品進(jìn)行設(shè)計(jì)之前,必須先確定人們是否需要這種產(chǎn)品。
應(yīng)當(dāng)把機(jī)械設(shè)計(jì)看成是機(jī)械設(shè)計(jì)人員運(yùn)用創(chuàng)造性的才能進(jìn)行產(chǎn)品設(shè)計(jì)、系統(tǒng)分析和制定產(chǎn)品的制造工藝學(xué)的一個(gè)良機(jī)。掌握工程基礎(chǔ)知識要比熟記一些數(shù)據(jù)和公式更為重要。僅僅使用數(shù)據(jù)和公式是不足以在一個(gè)好的設(shè)計(jì)中做出所需的全部決定的。另一方面,應(yīng)該認(rèn)真精確的進(jìn)行所有運(yùn)算。例如,即使將一個(gè)小數(shù)點(diǎn)的位置放錯(cuò),也會使正確的設(shè)計(jì)變成錯(cuò)誤的。
一個(gè)好的設(shè)計(jì)人員應(yīng)該勇于提出新的想法,而且愿意承擔(dān)一定的風(fēng)險(xiǎn),當(dāng)新的方法不適用時(shí),就使用原來的方法。因此,設(shè)計(jì)人員必須要有耐心,因?yàn)?所花費(fèi)的時(shí)間和努力并不能保證帶來成功。一個(gè)全新的設(shè)計(jì),要求屏棄許多陳舊的,為人們所熟知的方法。由于許多人墨守成規(guī),這樣做并不是一件容易的事。一位機(jī)械設(shè)計(jì)師應(yīng)該不斷地探索改進(jìn)現(xiàn)有的產(chǎn)品的方法,在此過程中應(yīng)該認(rèn)真選擇原有的、經(jīng)過驗(yàn)證的設(shè)計(jì)原理,將其與未經(jīng)過驗(yàn)證的新觀念結(jié)合起來。
2
Goldschmidt的工作是建立在建筑的方面,包含了深刻的見解。她指出設(shè)計(jì)師總是使用通過畫草圖使意象生成的新形式的組合。同時(shí),她補(bǔ)充說,至關(guān)重要的是設(shè)計(jì)師們也必須在相反的過程,即在他們的腦海里用他們素描生成圖像的形式。她斷言,通過互動意象素描是一種合理的推理模式,通過系統(tǒng)概念和音形參數(shù)之間的交流。
很明顯,從藝術(shù)領(lǐng)域到工程領(lǐng)域,幾乎所有的設(shè)計(jì)師都需要可視化的設(shè)計(jì)方式。然而,區(qū)分視覺設(shè)計(jì)的表述方法很重要:哪些是以交流為目的的通信(與客戶、同事或利害關(guān)系人),哪些是用于評價(jià)設(shè)計(jì)的質(zhì)量。以上兩者都不是由視覺設(shè)計(jì)的意義,相對其描述,它應(yīng)該是促使新思想的產(chǎn)生、推理以及便于找出引發(fā)它們的創(chuàng)作的設(shè)計(jì)形式。
草圖設(shè)計(jì)在解決創(chuàng)造性、探索性、無期限待解決問題上,通過側(cè)面的轉(zhuǎn)換發(fā)揮了重要的作用。正如加納記錄的,通過設(shè)計(jì)和以草圖的形式構(gòu)建的繪畫的表示方法,因?yàn)槠湓谝环矫婵梢哉碛行蛞子诶斫?而另一方面他們又對解釋的含糊不清。關(guān)鍵是這種方法非常缺乏明確性。很明顯,有很多的研究,對現(xiàn)有的概念草圖,目的是以電腦為依托,通過媒體實(shí)現(xiàn)目的和潛力。然而,關(guān)于直接用于汽車概念草圖的研究很少,是否有足夠的能力支持生產(chǎn)和他們計(jì)算機(jī)的使用。在工業(yè)領(lǐng)域和CAD有關(guān)的,在一個(gè)越來越大的壓力下,減少訂貨至交貨的時(shí)間仍然是一個(gè)待研究的領(lǐng)域。
3
新材料如雙相鋼或鋁復(fù)雜的幾何形狀的工業(yè)零件增加獲得無缺陷部分的沖壓的困難。一個(gè)更好的解決之道是調(diào)節(jié)壓邊壓力。我們的工作是根據(jù)H?ussermann和Haller原來的想法。我們的目標(biāo)是控制運(yùn)動下的壓邊的空白。有了可變形的柔性壓邊,有可能創(chuàng)造一些獨(dú)立的區(qū)域。在每個(gè)區(qū)域中,一個(gè)壓邊力可以施加在片材上,因此,一個(gè)強(qiáng)大的力可容納空白區(qū),和一個(gè)較小的空白區(qū),可以讓這個(gè)力在另一個(gè)區(qū)域中移動。關(guān)于前門板壓邊力的優(yōu)化一些方法以及一些解決結(jié)果,通常使用數(shù)值模擬進(jìn)行ABAQUS明確,有限的參數(shù)元模型(網(wǎng)格密度,沖擊速度)用最少的仿真時(shí)間達(dá)到良好的預(yù)測。 定義目標(biāo)函數(shù),以盡量減少沖頭的工作。 3個(gè)不等式約束函數(shù)的定義是為了避免頸縮起皺。為了避免縮頸,坯料的主要應(yīng)力是有限的值,這是確定通過使用修改過的最大的力標(biāo)準(zhǔn)(MMFC)。Labergere提出,為了避免起皺,要在下壓邊,角之間的壓邊的空白的表面和一個(gè)元件被限制在由用戶設(shè)定的值。然而,它是由Batoz提出,在工件的有用部分,主要的應(yīng)力被限制到一個(gè)值。最佳的本地化,我們使用了響應(yīng)面法彌漫性近似計(jì)算,再加上一個(gè)適應(yīng)性的策略,以更新的研究空間。
4
本文從一個(gè)簡單的介紹,關(guān)于金屬板材成形數(shù)值模擬的必要性和復(fù)雜的汽車覆蓋件成形,有限元分析(FEA),這是一個(gè)功能強(qiáng)大的仿真工具,用于分析復(fù)雜的三維金屬板材成形問題,以及它們的動態(tài)顯式有限元方法的原理及特點(diǎn),本文介紹和討論了現(xiàn)有的各種商業(yè)有限元方法代碼用于金屬板材成形數(shù)值模擬在世界,國內(nèi)和國際地位的汽車覆蓋件仿真。前門外板的一個(gè)一定的新車被視為作為一個(gè)例子,動態(tài)顯式有限元代碼。 Dynaform軟件用于在前門的外板形成過程的仿真。如破裂過程中的缺陷進(jìn)行了預(yù)測。改進(jìn)方法可以幫助解決仿真結(jié)果。金屬板材成形模擬的前景概述。
附錄
1
“The machine design is through designs the new product or improves the old product to meet the human need the application technical science. It involves the project technology each domain, mainly studies the product the size, the shape and the detailed structure basic idea, but also must study the product the personnel which in aspect the and so on manufacture, sale and use question.
Carries on each kind of machine design work to be usually called designs the personnel or machine design engineer. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineering material, materials mechanics and machine manufacture technology has the deep elementary knowledge.
If front sues, the machine design goal is the production can meet the human need the product. The invention, the discovery and technical knowledge itself certainly not necessarily can bring the advantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of product.
Must regard as the machine design is the machine design personnel carries on using creative ability the product design, the system analysis and a formulation product manufacture technology good opportunity. Grasps the project elementary knowledge to have to memorize some data and the formula is more important than. The merely service data and the formula is insufficient to the completely decision which makes in a good design needs. On the other hand, should be earnest precisely carries on all operations. For example, even if places wrong a decimal point position, also can cause the correct design to turn wrongly.
A good design personnel should dare to propose the new idea, moreover is willing to undertake the certain risk, when the new method is not suitable, use original method. Therefore, designs the personnel to have to have to have the patience, because spends the time and the endeavor certainly cannot guarantee brings successfully. A brand-new design, the request screen abandons absolutely many, knows very well the method for the people. Because many person of conservativeness, does this certainly is not an easy matter. A mechanical designer should unceasingly explore the improvement existing product the method, should earnestly choose originally, the process confirmation principle of design in this process, with has not unified it after the confirmation new idea.”
2
“The work of Goldschmidt in this area, also based on architecture, is telling, and contains powerful insights. She deduces that designers invariably use imagery to generate new form combinations that they represent through sketching. Crucially, she adds that they also work in the opposite way; they sketch to generate images of forms in their minds. She asserts that interactive imagery through sketching is a rational mode of reasoning characterized by systematic exchanges between conceptual and figural arguments.
It is clear that the need for visualization is recognized by almost all designers in diverse fields, from the arts to engineering. However, it is important to distinguish between that visual representation which is for the purposes of communication (with clients, colleagues or other interested parties) and that which is used for evaluation; that is to assess the quality of the design. Neither of these is what is meant by visual thinking. Rather it is the generation of new ideas, the reasoning that gives rise to them and facilitates the creation of form in designs (as opposed to their presentation).
Sketches play an important role in the creative, explorative, open-ended phase of problem solving, facilitated by lateral transformations. As Garner notes: Pictorial representations, constructed during designing and taking the form of sketches, are important to designing because they impose both order and tangibility on the one hand, while on the other hand their ambiguity stimulates re-interpretation. The very lack of clarity may be important. It is apparent that there is a wealth of existing research concerning the concept sketch; the purpose it has, the media through which it is achieved and its potential for being supported by computers. There is, however, very little research directly pertaining to the automotive concept sketch and whether it is possible to support the production and use of them using computers. In an industry heavily committed to CAD and where there is an increasing pressure to reduce lead times it is an area full of research opportunity”
3
“New materials such as dual phase steel or aluminum and complex geometries of industrial parts increase the difficulties to obtain a defect free part by stamping. One way of solution is a better regulation of the blank holder pressures. Our work is based on an original idea of Siegert, H?ussermann and Haller [1, 2, 3]. The goal is to control the movement of the blank under the blank holder. Thanks to a deformable flexible blank holder, it is possible to create some independent zones. In each zone, a blank holder force can be applied on the sheet, so that a strong force can hold the blank in a zone, and a smaller one can let it move in another zone. The methodology is presented as well as some results dealing with the optimization of the blank holder force considering the drawing of a front door panel (Numisheet’99 benchmark test). The numerical simulations are performed using ABAQUS Explicit. The parameters of the finite element model (mesh density, speed of punch) are set to achieve a good prediction with a minimum simulation time. The objective function is defined to minimize the work of the punch. Three inequality constraints functions were defined to avoid necking and wrinkling. To avoid necking, the major stress of the blank is limited to a value, which is determined by using the modified maximum force criterion (MMFC) [4]. To avoid wrinkling, under the blank holder, the angle between the blank holder surface and an element of the blank is limited to a value set by the user, as proposed by Gelin and Labergere [5]. However, in the useful part of the workpiece, the major stress is limited to a value, which was proposed by Brunet, Batoz and Bouabdallah [6]. For the localization of the optimum, we use a response surface method computed with a diffuse approximation and coupled with an adaptative strategy to update the research space.”
4
“The paper starts with a brief overview to the necessity of sheet metal forming simulation and the complexity of automobile panel forming, then leads to finite element analysis (FEA) which is a powerful simulation tool for analyzing complex three-dimensional sheet metal forming problems. The theory and features of the dynamic explicit finite element methods are introduced and the available various commercial finite element method codes used for sheet metal forming simulation in the world are discussed, and the civil and international status of automobile panel simulation as well. The front door outer panel of one certain new automobile is regarded as one example that the dynamic explicit FEM code. Dynaform is used for the simulation of the front door outer panel forming process. Process defects such as ruptures are predicted. The improving methods can be given according to the simulation results. Foreground of sheet metal forming simulation is outlined.”
參考文獻(xiàn):
[1]桂慧.機(jī)械專業(yè)英語. 國防工業(yè)出版社.2009
[2]M. Tovey and S. Porter, School of Art and Design ,Coventry University ,Priory St .,Coventry . Sketching, concept development and automotive design.
[3]張揚(yáng).連洪.李雙義.王洪志.板料成形模擬及其在汽車覆蓋件沖壓過程中的應(yīng)用. 中國科學(xué)院上海冶金研究所.材料物理與化學(xué)(專業(yè)) 博士論文 2000