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1、附件1:外文資料翻譯譯文 The finite element analysis system development present situation and prospect Ravichandra Patchigolla and Yesh P. Singh Along with the development of modern science and technology, people are constantly build more fast traffic tools, larger buildings, the more big span Br
2、idges, the more power generator sets and more precision mechanical equipment. All these require engineer in the designing phase can accurately predict products and engineering technical performance, need to structure strength and static and dynamic temperature field, flow field, electromagnetic fiel
3、d and seepage analysis of technical parameters. For example analysis and calculation of the high-rise buildings and large span bridge during an earthquake, look at the implications will happen destructive accidents; Analysis and calculation of the temperature field of nuclear reactors, determine whe
4、ther reasonable heat transfer and cooling system; Analysis of fluid dynamics in turbine blade, in order to improve the operation parameters of efficiency. These can be summed up in solving physical control problems partial differential equations is often impossible. In recent years in the computer t
5、echnology and the numerical Analysis method supports developed under Finite Element Analysis (FEA) method and Finite Element, order is to solve the complicated engineering Analysis and calculation problem which provides an effective way. Our country of the ninth five-year plan period in promoting CA
6、D technology, mechanical industry from the prevalence rate of large and medium-sized enterprises CAD 20% of the five-year "end" raised to current 70%. Along with the enterprise CAD widely applied, Engineering and technical personnel, and already gradually dump board will focus in how to optimize the
7、 design, improve product quality, Engineering and Computer Aided Engineering analysis (CAE, Computer software and applicants Engineering) method will be the key technical factors. In engineering practice, finite element analysis software and the integrated application of CAD system make the design l
8、evel occurred a qualitative leap, mainly displays in the following aspects: to increase the design function, reduce design cost; ? shorten design and analysis of cycle; ? increase the reliability of products and engineering; ? adopting the optimization design, reduce material consumption or co
9、st; ? in products manufacturing or engineering construction advance found potential problem; ? simulate various test plan to reduce the time and money; ? mechanical accident analysis, found out the cause of the accident. In promoting CAD technology today, from his bike to the space shuttle,
10、all the design manufacture is inseparable from the finite element calculation and analysis, in the engineering design and analysis FEA will get more and more extensive attention. Below is the San Francisco bay bridge seismic response analysis of finite element analysis model. Development direction
11、 and significant progress in early 20th century world at the end of the 1950s and early 1960s invested a lot of manpower and material resources development with powerful features of finite element analysis program. One of the most famous is by NASA (NASA) in 1965 entruststhe American computing scien
12、ce company and bel air system company developed the NASTRAN finite element analysis system. This system have been developed dozens of version, is the worlds largest, the strongest function finite element analysis system. From then to now, the worlds research institutions and universities are develop
13、ing a batch of smaller but flexible, price lower special or general finite element analysis software, mainly in Germany PAFEC ASKA, British, French SYSTUS, American ABQUS, ADINA, ANSYS, BERSAFE, BOSOR COSMOS, ELAS, MARC, STARDYNE etc products with. Todays international development of the FEA method
14、and software shows the following some trends features: 1 from the pure structure mechanics calculation development to solve many problems of physical field finite element analysis method (from structured matrix analysis, evolved gradually extended to board, shell and entity etc continuum solid mec
15、hanics analysis, the practice has proved it is a very efficient numerical analysis method. And theoretically has also proof, as long as the unit used for solving the object of discrete small enough income can be enough solution in precision value approach. So in recent years has progressed to finite
16、 element method of fluid mechanics, temperature field, electric conduction, magnetic field, seepage and problems solving calculation of acoustic, and recently developed to solve several interdisciplinary problem. For example when air flows through a high tower, and the deformation of the tower in tu
17、rn affect deformation airflow flow... This needs with solid mechanics and fluid dynamic finite element analysis results cross, the so-called "iteration fluidsolid coupled" problem. 2 by solving linear engineering problems progressed to the analysis nonlinear problems with the development of scienc
18、e and technology, linear theory has far cant meet the design requirements. For example the high-rise building and construction industry, the emergence of large-span suspension bridge is asked to consider structure of large displacement and large strain etc geometrically nonlinear; Aerospace and powe
19、r engineering of high temperature parts existing thermal deformation and thermal stress, also want to consider material nonlinear problem; Such as plastic, rubber and composite materials, etc. Various kinds of new material appears, only on linear computation theory would not be sufficient to solve t
20、he problems of using nonlinear finite element algorithm, only to solve. As is known to all, nonlinear numerical calculation is very complex, it involves a lot of special mathematics problems and operation skill, hard as general engineering technicians hands. Therefore in recent years abroad some com
21、pany has spent a lot of manpower and investment and development such as MARC, ABQUS and ADINA specializes in solving nonlinear problems such as the finite element analysis software, and widely used in engineering practice. These software in common is efficient nonlinear solver and rich and practical
22、 nonlinear CaiLiaoKu. 3 enhance visual lead modeling and rear data processing functions early finite element analysis software research emphasis on solving method is a new high efficiency and high accuracy unit. Along with the gradual improvement method of numerical analysis, particularly the rapi
23、d development of computer operation speed, the whole calculation system for solving operations less time, and data preparation and operation result performance problem is getting more and more outstanding. In todays engineering workstation, solving a contains 10 million equation with the finite elem
24、ent model requires only a few minutes. But if use manual way to build the model, and then the calculation result is handling large amounts of time needs a few weeks. It is no exaggeration to say, engineers in analysis and calculation have an engineering problem more than 80% of the energy is spent o
25、n data preparation and analysis of the results. So now almost all the commercial finite element program system has powerful lead modeling and rear data processing module. In emphasizing "visual" today, many procedures are established to very User friendly GUI (with), little User with visual graphic
26、User can quickly way grid directly generate finite element analysis, automatic dividing the data, and required the amount of calculation results consolidation deformation figure, equivalent to cloud, facilitate extremum distribution list of search and required data output. 4 and seamless integrati
27、on of CAD software of finite element analysis system today with general another characteristic is the integration of CAD software in use namely, complete with CAD software components and parts after the modelling design, automatically generating finite element mesh and calculate, if the analysis res
28、ults do not comply with the design requirements are calculated to restart modelling and, until satisfaction, thus greatly improve the design level and efficiency. Today, engineers can in the integration of CAD and FEA software environment quickly solve a in the past can deal with complex engineering
29、 analysis problem. So todays all commercial finite element system developed and famous auto-producers CAD software (for example Pro/e, SolidEdge, SolidWorks Unigraphics, Bentley and AutoCAD, IDEAS, etc) interface. 5 in the development of the Wintel platform of early finite element analysis softwar
30、e are basically in large and medium-sized computers (mainly Mainframe) on the development or operation, and later developed to Engineering workstations (EWS, Engineering WorkStation) as a platform, their common characteristic is all adopt the UNIX operating system. The PC has made the application of
31、 computer fundamental changes happened on her desk, the engineer eager to finish complex engineering analysis dreams to become a reality. But early PC using 16-bit CPU and DOS operating system, the memory data block limited public, so was the size of the calculation model should not exceed 1 000 ord
32、er equation. Microsoft Windows operating system and the Intel Pentium processor 32-bit for will launch the PC provides necessary for finite element analysis software and hardware of the support platform. Therefore the internationally famous finite element program research and development institution
33、s have their software shifted to the Wintel platform. The table below lists the ADINA V7.3 version with the PCs Windows NT environment and SGI workstation and four engineering example calculated the time needed to solve. It shows the latest high-grade PC already and the solving ability of neck-and-n
34、eck EWS cheap. Table V7.3 edition ADINA running time of several machines comparison Characteristics of computational problems Equation several NEQ Running time (in seconds) PentiumII450MHZ PentiumIII450MHZ Engineering workstations Nonlinear 3d contact (calculation step) 51159 2
35、19 188 219 Linear static analysis 58707 262 234 249 Dynamic analysis frequency calculation 31205 311 258 287 Three-dimensional flow analysis 36162 218 183 208 For large and medium-sized computers and EWS in developed on finite element program shifted to PE machine
36、, often need to adopt the Hummingbird company Exceed a simulation software. The result more troublesome, and cant make full use of the PC software and hardware resources. So recently some companies, such as IDEAS, ADINA and R&D began in Windows platform development finite element program, called "Na
37、tive Windows" versions, and on their PCS in the Linux operating system environment development of finite element program packages. Domestic development situation and prospects of the United States in 1979 SAP5 linear structure static, dynamic analysis program to introduce transplant success, domes
38、tic application lifted the universal finite element program to the climax of the analysis and calculation of engineering problems. The climax continued until 1981 ADINA nonlinear structural analysis program has been introduced, at that time many cannot solve engineering problems are solved. Everybod
39、y also began to understand the finite element analysis program is really engineer for the analysis of the application of computer the important tool. But was limited to domestic large and medium-sized computers seldom, only about the hangzhou steam turbine factory Siemens7738 and shenyang blower fac
40、tory IBM4310 installation of the program, so the user calculate very inconvenient and expensive. PCs emergence and its performance miraculously enhance, for transplantation and development PC version of the finite element program provides the necessary operation platform. Say the development of dome
41、stic FEA is always fuss around PC platforms. In domestic development more successful and have more users (100 more) finite element analysis system has dalian university of technology FIFEX95, the department of engineering force of Beijing university of science and engineering mechanics SAP84, China
42、academy of machinery science MAS5.0 and hangzhou automation technology institute MFEP4. 0, etc. But as described above, foreign many famous finite element analysis company has shrugged off to a PC platform from years of development for keen, change the FEA program developers development domestic PC
43、version, and should no longer has the advantage from the following several aspects effort: 1 research and development solution of a solid mechanics and interdisciplinary FEA program after decades of research and development, and to solve the finite element method and the solid mechanics software h
44、as more mature, now the forefront of research problem is fluid dynamics, compressible and non-compressible fluid flow from solid mechanics and interdisciplinary problem. No similar functions to the domestic commercial software, so foreign software, they sell very expensive. In order to break the mon
45、opoly situation, we must develop have independent copyright, used to analyze the fluid is not solid mechanics and interdisciplinary software. Because fluid mechanics problem is far more complex than solid and rarely have a ready-made software can reference, therefore requires a lot of manpower and f
46、unds. It must have countries and large enterprise groups to support. 2 development with Chinese characteristics automatic modeling technology and GUI development modeling technology and the investment than mere the foregoing subject to GUI much less, but can greatly improve the performance of the
47、FEA software and user acceptance, thus plays twice the result with half the effort. The domestic many people in this respect did a lot of work, but it was the PC graphics support environment is limited, therefore the development effect be not all very ideal. Windows provides for OpenGL graphics stan
48、dard, PC application in visual graphics technology to developing GUI provides powerful tools. Todays international OpenGL is generally recognized high-performance graphics and interactive visual processing standards, apply it to the 3d graphics software developed by the endearment of professional an
49、d technical personnel in the world, now dominant computer companies have adopted this standard. As mentioned, in recent years the FEA program has cast abroad some simulation software, directly on Windows platform development finite element program. Hangzhou automation technology institute 1997-1999
50、using OpenGL graphics standard and the corresponding Visual c + + programming tools, such as in PC successfully developed a set of visualization finite element program packages. It can directly through the "menu", "the window", "dialog box" and "icon" visual graphic pictures and symbols such as the
51、operation, automatic establish finite element analysis model in an interactive method, and the calculation results of the type of realizing, and visualization processor can greatly improve the efficiency of limited the analysis and accuracy, also facilitate the user study and control. 3 and has th
52、e independent copyright in front of CAD software integration today had been told, an important feature of the finite element method and seamless integration of CAD software. As the development of our country proper motion, firstly, we must consider the FEA program and our independent copyright CAD s
53、oftware integration. Because the finite element analysis is mainly used in shape more complex components, so want to and with three-dimensional modeling functions and CAD software integration, which makes the design and analysis of combine closely, as a whole. 2:外文原文(復(fù)印件) 有限元分析系統(tǒng)的發(fā)展現(xiàn)狀與展望 隨著
54、現(xiàn)代科學(xué)技術(shù)的發(fā)展,人們正在不斷建造更為快速的交通工具、更大規(guī)模的建筑物、更大跨度的橋梁、更大功率的發(fā)電機組和更為精密的機械設(shè)備。這一切都要求工程師在設(shè)計階段就能精確地預(yù)測出產(chǎn)品和工程的技術(shù)性能,需要對結(jié)構(gòu)的靜、動力強度以及溫度場、流場、電磁場和滲流等技術(shù)參數(shù)進行分析計算。例如分析計算高層建筑和大跨度橋梁在地震時所受到的影響,看看是否會發(fā)生破壞性事故;分析計算核反應(yīng)堆的溫度場,確定傳熱和冷卻系統(tǒng)是否合理;分析渦輪機葉片內(nèi)的流體動力學(xué)參數(shù),以提高其運轉(zhuǎn)效率。這些都可歸結(jié)為求解物理問題的控制偏微分方程式往往是不可能的。近年來在計算機技術(shù)和數(shù)值分析方法支持下發(fā)展起來的有限元分析(FEA,F(xiàn)inite
55、 Element Analysis)方法則為解決這些復(fù)雜的工程分析計算問題提供了有效的途徑。我國在"九五"計劃期間大力推廣CAD技術(shù),機械行業(yè)大中型企業(yè)CAD的普及率從"八五"末的20%提高到目前的70%。隨著企業(yè)CAD應(yīng)用的普及,工程技術(shù)人員已逐步甩掉圖板,而將主要精力投身如何優(yōu)化設(shè)計,提高工程和產(chǎn)品質(zhì)量,計算機輔助工程分析(CAE,Computer Aided Engineering)方法和軟件將成為關(guān)鍵的技術(shù)要素。在工程實踐中,有限元分析軟件與CAD系統(tǒng)的集成應(yīng)用使設(shè)計水平發(fā)生了質(zhì)的飛躍,主要表現(xiàn)在以下幾個方面:增加設(shè)計功能,減少設(shè)計成本; ?縮短設(shè)計和分析的循環(huán)周期; ?增加產(chǎn)品
56、和工程的可靠性; ?采用優(yōu)化設(shè)計,降低材料的消耗或成本; ?在產(chǎn)品制造或工程施工前預(yù)先發(fā)現(xiàn)潛在的問題; ?模擬各種試驗方案,減少試驗時間和經(jīng)費; ?進行機械事故分析,查找事故原因。 在大力推廣CAD技術(shù)的今天,從自行車到航天飛機,所有的設(shè)計制造都離不開有限元分析計算,F(xiàn)EA在工程設(shè)計和分析中將得到越來越廣泛的重視。下圖是美國舊金山海灣大橋地震響應(yīng)計算的有限元分析模型。 發(fā)展方向及重大進展國際上早20世紀在50年代末、60年代初就投入大量的人力和物力開發(fā)具有強大功能的有限元分析程序。其中最為著名的是由美國國家宇航局(NASA)在1965年委托美國計算科學(xué)
57、公司和貝爾航空系統(tǒng)公司開發(fā)的NASTRAN有限元分析系統(tǒng)。該系統(tǒng)發(fā)展至今已有幾十個版本,是目前世界上規(guī)模最大、功能最強的有限元分析系統(tǒng)。從那時到現(xiàn)在,世界各地的研究機構(gòu)和大學(xué)也發(fā)展了一批規(guī)模較小但使用靈活、價格較低的專用或通用有限元分析軟件,主要有德國的ASKA、英國的PAFEC、法國的SYSTUS、美國的ABQUS、ADINA、ANSYS、BERSAFE、BOSOR、COSMOS、ELAS、MARC和STARDYNE等公司的產(chǎn)品。當今國際上FEA方法和軟件發(fā)展呈現(xiàn)出以下一些趨勢特征: 1 從單純的結(jié)構(gòu)力學(xué)計算發(fā)展到求解許多物理場問題有限元分析方法最早是從結(jié)構(gòu)化矩陣分析發(fā)展而來,逐步
58、推廣到板、殼和實體等連續(xù)體固體力學(xué)分析,實踐證明這是一種非常有效的數(shù)值分析方法。而且從理論上也已經(jīng)證明,只要用于離散求解對象的單元足夠小,所得的解就可足夠逼近于精確值。所以近年來有限元方法已發(fā)展到流體力學(xué)、溫度場、電傳導(dǎo)、磁場、滲流和聲場等問題的求解計算,最近又發(fā)展到求解幾個交叉學(xué)科的問題。例如當氣流流過一個很高的鐵塔產(chǎn)生變形,而塔的變形又反過來影響到氣流的流動……這就需要用固體力學(xué)和流體動力學(xué)的有限元分析結(jié)果交叉迭代求解,即所謂"流固耦合"的問題。 2 由求解線性工程問題進展到分析非線性問題隨著科學(xué)技術(shù)的發(fā)展,線性理論已經(jīng)遠遠不能滿足設(shè)計的要求。例如建筑行業(yè)中的高層建筑和大跨度懸索
59、橋的出現(xiàn),就要求考慮結(jié)構(gòu)的大位移和大應(yīng)變等幾何非線性問題;航天和動力工程的高溫部件存在熱變形和熱應(yīng)力,也要考慮材料的非線性問題;諸如塑料、橡膠和復(fù)合材料等各種新材料的出現(xiàn),僅靠線性計算理論就不足以解決遇到的問題,只有采用非線性有限元算法才能解決。眾所周知,非線性的數(shù)值計算是很復(fù)雜的,它涉及到很多專門的數(shù)學(xué)問題和運算技巧,很難為一般工程技術(shù)人員所掌握。為此近年來國外一些公司花費了大量的人力和投資開發(fā)諸如MARC、ABQUS和ADINA等專長于求解非線性問題的有限元分析軟件,并廣泛應(yīng)用于工程實踐。這些軟件的共同特點是具有高效的非線性求解器以及豐富和實用的非線性材料庫。 3 增強可視化的前
60、置建模和后置數(shù)據(jù)處理功能早期有限元分析軟件的研究重點在于推導(dǎo)新的高效率求解方法和高精度的單元。隨著數(shù)值分析方法的逐步完善,尤其是計算機運算速度的飛速發(fā)展,整個計算系統(tǒng)用于求解運算的時間越來越少,而數(shù)據(jù)準備和運算結(jié)果的表現(xiàn)問題卻日益突出。在現(xiàn)在的工程工作站上,求解一個包含10萬個方程的有限元模型只需要用幾十分鐘。但是如果用手工方式來建立這個模型,然后再處理大量的計算結(jié)果則需用幾周的時間??梢院敛豢鋸埖卣f,工程師在分析計算一個工程問題時有80%以上的精力都花在數(shù)據(jù)準備和結(jié)果分析上。因此目前幾乎所有的商業(yè)化有限元程序系統(tǒng)都有功能很強的前置建模和后置數(shù)據(jù)處理模塊。在強調(diào)"可視化"的今天,很多程序都建立
61、了對用戶非常友好的GUI(Graphics User Interface),使用戶能以可視圖形方式直觀快速地進行網(wǎng)格自動劃分,生成有限元分析所需數(shù)據(jù),并按要求將大量的計算結(jié)果整理成變形圖、等值分布云圖,便于極值搜索和所需數(shù)據(jù)的列表輸出。 4 與CAD軟件的無縫集成當今有限元分析系統(tǒng)的另一個特點是與通用CAD軟件的集成使用 即,在用CAD軟件完成部件和零件的造型設(shè)計后,自動生成有限元網(wǎng)格并進行計算,如果分析的結(jié)果不符合設(shè)計要求則重新進行造型和計算,直到滿意為止,從而極大地提高了設(shè)計水平和效率。今天,工程師可以在集成的CAD和FEA軟件環(huán)境中快捷地解決一個在以前無法應(yīng)付的復(fù)雜工程分析問題
62、。所以當今所有的商業(yè)化有限元系統(tǒng)商都開發(fā)了和著名的CAD軟件(例如Pro/ENGINEER、Unigraphics、SolidEdge、SolidWorks、IDEAS、Bentley和AutoCAD等)的接口。 5 在Wintel平臺上的發(fā)展早期的有限元分析軟件基本上都是在大中型計算機(主要是Mainframe)上開發(fā)和運行的,后來又發(fā)展到以工程工作站(EWS,Engineering WorkStation)為平臺,它們的共同特點都是采用UNIX操作系統(tǒng)。PC機的出現(xiàn)使計算機的應(yīng)用發(fā)生了根本性的變化,工程師渴望在辦公桌上完成復(fù)雜工程分析的夢想成為現(xiàn)實。但是早期的PC機采用16位CP
63、U和DOS操作系統(tǒng),內(nèi)存中的公共數(shù)據(jù)塊受到限制,因此當時計算模型的規(guī)模不能超過1萬階方程。Microsoft Windows操作系統(tǒng)和32位的Intel Pentium處理器的推出為將PC機用于有限元分析提供了必需的軟件和硬件支撐平臺。因此當前國際上著名的有限元程序研究和發(fā)展機構(gòu)都紛紛將他們的軟件移值到Wintel平臺上。下表列出了用ADINA V7.3版在PC機的Windows NT環(huán)境和SGI工作站上同時計算4個工程實例所需要的求解時間。從中可以看出最新高檔PC機的求解能力已和中低檔的EWS不相上下?! ? 表 ADINA V7.3版幾種機器上的運行時間比較 計算問題的特
64、征 方程數(shù)NEQ 運行時間(秒) PentiumII450MHZ PentiumIII450MHZ 工程工作站 非線性三維接觸 (計算一步) 51159 219 188 219 線性靜力分析 58707 262 234 249 動力分析頻率計算 31205 311 258 287 三維流動分析 36162 218 183 208 為了將在大中型計算機和EWS上開發(fā)的有限元程序移值到PE機上,常常需要采用Hummingbird公司的一個仿真軟件Exceed。這樣做的結(jié)果比較麻煩,而且不
65、能充分利用PC機的軟硬件資源。所以最近有些公司,例如IDEAS、ADINA和R&D開始在Windows平臺上開發(fā)有限元程序,稱作"Native Windows"版本,同時還有在PC機上的Linux操作系統(tǒng)環(huán)境中開發(fā)的有限元程序包。 國內(nèi)發(fā)展情況和前景1979年美國的SAP5線性結(jié)構(gòu)靜、動力分析程序向國內(nèi)引進移植成功,掀起了應(yīng)用通用有限元程序來分析計算工程問題的高潮。這個高潮一直持續(xù)到1981年ADINA非線性結(jié)構(gòu)分析程序引進,一時間許多一直無法解決的工程難題都迎刃而解了。大家也都開始認識到有限元分析程序的確是工程師應(yīng)用計算機進行分析計算的重要工具。但是當時限于國內(nèi)大中型計算機很少,大
66、約只有杭州汽輪機廠的Siemens7738和沈陽鼓風(fēng)機廠的IBM4310安裝有上述程序,所以用戶算題非常不方便,而且費用昂貴。PC機的出現(xiàn)及其性能奇跡般的提高,為移植和發(fā)展PC版本的有限元程序提供了必要的運行平臺。可以說國內(nèi)FEA軟件的發(fā)展一直是圍繞著PC平臺做文章。在國內(nèi)開發(fā)比較成功并擁有較多用戶(100家以上)的有限元分析系統(tǒng)有大連理工大學(xué)工程力學(xué)系的FIFEX95、北京大學(xué)力學(xué)與科學(xué)工程系的SAP84、中國農(nóng)機科學(xué)研究院的MAS5.0和杭州自動化技術(shù)研究院的MFEP4. 0等。但正如上面所述,國外很多著名的有限元分析公司已經(jīng)從前些年對PC平臺不屑一顧轉(zhuǎn)變?yōu)闊嶂园l(fā)展,對國內(nèi)FEA程序開發(fā)者來說發(fā)展PC版本不再具有優(yōu)勢,而應(yīng)該從下面幾方面加以努力: 1 研究開發(fā)求解非固體力學(xué)和交叉學(xué)科的FEA程序經(jīng)過幾十年的研究和發(fā)展,用于求解固體力學(xué)的有限元方法和軟件已經(jīng)比較成熟,現(xiàn)在研究的前沿問題是流體動力學(xué)、可壓縮和不可壓縮流體的流動等非固體力學(xué)和交叉學(xué)科的問題。由于國內(nèi)沒有類似功能的商品化軟件,所以國外的軟件就賣得非常貴。為了破這種壟斷局面,我們必須發(fā)展有自主版權(quán)
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