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1、<p><b> 外文翻譯</b></p><p> Hydorgen storage in wind turbine towers</p><p> International Journal of Hydrogen Energy 29 (2004) 1277–1288 www.elsevier.com Ryan Kottenstettea, Jas
2、on Cotrellb; aSummer intern from Santa Clara University, 1235 Monroe St, Santa Clara, CA 95050, USA National Wind Technology Centre, National Renewable Energy Laboratory, 1614 Cole Blvd, Golden, CO 80401, USA Received 18
3、 November 2003; accepted 15 December 2003 </p><p> Abstract: Modern utility-scale wind turbine towers are typically conical steel hydrogen in what we have termed a hydrogen tower. This paper examines potent
4、ial technical barriers to this technology and identi4es a minimum cost design. We discovered that hydrogen towers have a “crossover pressure” at which the critical mode of failure crosses over from fatigue to bursting. T
5、he crossover pressure for many turbine towers is between 1.0 and 1:5 mPa (approximately 10–15 atm) The hydrogen tower design </p><p> Keywords: Wind turbine; Tower; Hydrogen; Storage; Pressure vessel</p&
6、gt;<p> 1. Introduction</p><p> Low-cost hydrogen storage is recognized as a cornerstone of a renewables-hydrogen economy. Modern utility-scale wind turbine towers are typically conical steel struct
7、ures that, in addition to supporting the nacelle, could be used to store gaseous hydrogen. We have coined the phrase hydrogen tower to describe this technology. During hours, electrolyzers could use energy from the wind
8、turbines or the grid to generate hydrogen and store it in turbine towers. There are many potential uses for this s</p><p> (1) Identify the paramount considerations associated with using a wind turbine towe
9、r for hydrogen storage.</p><p> (2) Propose and analyze a cost ective design for a hydrogen tower.03603199/$ 30.00 Published by Elsevier Ltd on behalf of the International Association for Hydrogen Energy.&l
10、t;/p><p> (3) Compare the cost of storage in hydrogen towers to the cost of hydrogen dtorage storage in conwentional pressure vessels</p><p> There are many competitive methods of storing hydroge
11、n such as liquid hydrogen storage, underground geologic storage, and transmission pipeline storage. However, a comparison was made only to one storage technology to limit the scope of this study. Conventional pressure ve
12、ssel tech- nology was chosen because it is the most widely available of the technologies and the method most likely to be used for the moderate amounts of hydrogen storage considered in this study. This study engages the
13、se obje</p><p> 2. Benchmarks and assumptions</p><p> 2.1. Hydrogen generation</p><p> This study assumes electrolyzers generate the hydrogen to be stored in the hydrogen towers.
14、 As will later be demonstrated, the most economical pressures for storage in hydrogen towers are below 1:5 mPa. This study assumes that proton exchange membrane (PME) and high-pressure alkaline electrolyzers can produce
15、htdrogen up to this pressure without the use of an additional compressor</p><p> 2.2. Conventional towers</p><p> We chose to use the 1.5-MW tower model speci4ed in the WindPACT Advanced Wind
16、Turbine Designs Study as our baseline conventional tower This tower was modeled after a conventional tower built from four tapered, tubular, steel sections which are bolted together. Conventional towers are built by weld
17、ing together cylingenerally decrease in steps as the tower tapers to smaller diameters at higher elevations. For simplicity, the Wind PACT tower model instead assumes the wall thickness tapers in a smoo</p><p&
18、gt; 2.3. Conventional pressure vessels</p><p> Industrial pressure vessels for noncorrosive gases are of- ten built of carbon steel similar to that used in wind turbine tower construction. Although the mos
19、t economical pressure vessel geometry is long and slender, vessels are often limited by shipping constraints to a practical length of about 25m. This length limitation means that in order to better distribute the high 4x
20、ed costs associated with 4ttings and manways, pressure vessels are designed with relatively large diameters and high press</p><p> 3. Hydrogen tower considerations </p><p> Hydrogen storage cr
21、eates a number of additional considerations in wind turbine tower design. Accelerated at- mosphericcorrosion on the tower interior and hydrogen embrittlement may adversely aect the tower’s ductility, yield strength, and
22、fatigue life. Additionally, storing hydrogen at pressure signi4cantly increases the stresses on the tower. Therefore, wall reinforcement will likely be required. A structural analysis is required to evaluate how internal
23、 pressure may the tower’s design life.</p><p> 3.1. Corrosion</p><p> Both atmosphericcorrosion and hydrogen embrittlement will ect the interior of a hydrogen tower. Conventional wind turbine
24、towers are protected internally and externally from atmosphericcorrosion by paint. When a tower is used to store a pressurized gas, however, it becomes subject to the guidelines set forth in the American Society of Mecha
25、nical Engineers (ASME) Boiler and Pressure Vessel Code. The code states that paint is not an adequate form of protection for the interior of pressure vessels.</p><p> The product hydrogen (which would be fu
26、lly saturated with water vapor) could be dried to below the critical humidity level (less than 80% relative humidity) at minimal cost. Under these conditions, atmospheric corrosion would penetrate the steel’s surface at
27、the negligible rate of less than 0.01m per year </p><p> 3.2. Hydrogen attack</p><p> One of the two primary modes of corrosion failure when steel is exposed to a hydrogen environment is hydro
28、gen attack Although some sources do not distinguish hydrogen attack from hydrogen embrittlement (HE), other sources distinguish them by their diering responses to temperature. It is important not to confuse hydrogen atta
29、ck, a phenomenon that occurs only at high temperatures, with HE, a phenomenon that primarily damages materials at ambient temperatures. Hydrogen attack, also known as hydroge</p><p> 3.3. Hydrogen embrittle
30、ment</p><p> The term hydrogen embrittlement is commonly used to describe hydrogen environment embrittlement (HEE) and internal hydrogen embrittlement. HEE is caused by subjecting metal to a hydrogen-rich e
31、nvironment. During internal hydrogen embrittlement, hydrogen is produced inside a metal’s structure, usually by a processing technique and is unlikely to be relevant to hydrogen towers. The term hydrogen embrittlement wi
32、ll refer to HEE for the remainder of this paper. HEE is a process in which atomic hydro</p><p> Based on the considerations outlined above, the risk of HEE does not exclude the use of wind turbine towers fo
33、r hydrogen storage. It is, however, diLcult to compare the use of a wind turbine tower as a pressure vessel to more tra- ditional hydrogen applications because, unlike conventional pressure vessels, they are subjected to
34、 signi4cant dynamic loads inherent in wind turbine structures. The dynamic struc- tural loads applied to a turbine tower would serve to repeat- edly open micro4ssures, on</p><p> 3.4. Structural analysis<
35、;/p><p> Pressurizing the interior of a wind turbine tower creates unique structural demands. A pressurized tower must not only withstand loads caused by normal operation of the wind turbine, but it must also
36、ful4ll the requirements of a pres- sure vessel. Tubular towers for modern utility-scale wind turbines are typically limited by the fatigue strength of the horizontal welds. One primary concern, therefore, is the ef- fect
37、 of pressurizing the tower on the fatigue strength of these welds. In addition, </p><p> 3.5. Loads and stresses</p><p> Wind turbines are subjected to widely varying aerodynamicloads. These l
38、oads induce large bending moments that, in turn, cause tensile and compressive stresses paral lel to the axis of the tower (axial stresses). At the base of the tower, these stresses signi4cantly exceed the compres- sive
39、stresses caused by the weight of the turbine. Frequent, Auctuating aerodynamic loads seen during normal operation make fatigue the critical mode of failure for modern turbine towers. Subjecting a tower to inte</p>
40、<p> Based on the considerations outlined above, the risk of HEE does not exclude the use of wind turbine towers for hydrogen storage. It is, however, diLcult to compare the use of a wind turbine tower as a pressu
41、re vessel to more tra- ditional hydrogen applications because, unlike conventional pressure vessels, they are subjected to signi4cant dynamic loads inherent in wind turbine structures. The dynamic struc- tural loads appl
42、ied to a turbine tower would serve to repeat- edly open micro4ssures, on</p><p> 3.6. Crossover pressure</p><p> As the pressure rating of a hydrogen tower is increased, the primary mode of fa
43、ilure for the tower walls crosses over from fatigue to bursting. Once this “crossover” pressure is reached, the required wall thickness is determined by the maximum allowable hoop stress, rather than axial fatigue Fig.2s
44、hows required thickness as a function of pressure for both the fatigue and burst conditions. The solid set of lines describes thickness required at the base of the tower, and the dashed set of lines de</p><p&g
45、t; 儲氫的風(fēng)力渦輪機水塔</p><p> 發(fā)表于《國際期刊的氫能》(29期)(2004卷:1277至1288); </p><p> 瑞安,賈森撰實習(xí)時于美國夢露圣大學(xué), 1235年,在美國加州圣克拉拉國家可再生能源實驗室,2003年11月18日</p><p> 本文收稿為2003年12月15日。</p><p><b&g
46、t; 摘要:</b></p><p> 現(xiàn)代效用規(guī)模的風(fēng)力渦輪機塔通常采用錐形鋼結(jié)構(gòu),它可以用來存放工業(yè)氫氣,我們都稱之為氫塔。本文探討潛在渦輪機的技術(shù)壁壘,以這種技術(shù),并以最低成本設(shè)計此機器。我們發(fā)現(xiàn),氫塔存在一個"交叉壓力"。其中最為關(guān)鍵的是疲勞斷裂。交叉壓力—對許多渦輪塔是有限制的,大約為1.0和1.5兆帕斯卡(約10-15 ATM )。氫塔設(shè)計是在最便宜的儲氫利用率前提
47、下,來估算可用業(yè)務(wù)量的存儲和成本。其設(shè)計初衷是在小于交叉壓力的前提條件下,例如:一個84米高的氫塔將為1.5兆瓦汽輪機花費額外83000美元。它存放940公斤氫在1.1兆帕斯卡的壓力下。超出成本的傳統(tǒng)塔設(shè)備。由此產(chǎn)生,增量存儲費用為88美元每千克。</p><p> 關(guān)鍵詞:風(fēng)力發(fā)電機組、塔、氫氣、存儲壓力容器。</p><p><b> 1導(dǎo)言:</b><
48、/p><p> 低成本儲氫是公認(rèn)的一個基準(zhǔn)原則,一種可再生能源-氫經(jīng)濟(jì)。現(xiàn)代效用規(guī)模中的風(fēng)力發(fā)電機組的塔都是典型的圓錐形鋼結(jié)構(gòu),用氫塔來形容此項技術(shù)。電解槽可利用的能源來自風(fēng)能輪機,有許多潛在的用途為這個儲存燃油,儲存氫氣稍后可以被用來產(chǎn)生經(jīng)電力的燃料電池,在高峰用電需求時,這些能量可以受到遞減。另外,氫氣可用于燃料電池汽車或轉(zhuǎn)發(fā)給氣態(tài)氫管線。它是由李杰伊在美國國家可再生能源實驗室做的氫氣儲存在風(fēng)力渦輪塔實驗上總結(jié)
49、出來的結(jié)論。它提供大數(shù)額存儲風(fēng)力發(fā)電機組的部件,如電源電纜階梯,類似的思路和儲存氫氣在該基地-荷蘭愛因河岸上風(fēng)力渦輪是一樣的工作原理。目標(biāo)內(nèi)容如下: </p><p> ?。?)確定首要考慮相關(guān)因素,使用風(fēng)力發(fā)電機來儲氫。</p><p> ?。?)提出并分析成本,適當(dāng)做選擇性設(shè)計命名法:應(yīng)力幅、米、平均應(yīng)力、抗拉強度、屈服強度、面積、半徑、塔半徑、彎矩。</p>&l
50、t;p> ?。?)比較成本的存儲氫塔 成本儲氫在常規(guī)壓力下,有許多的方法儲存水力發(fā)電,比如液態(tài)氫儲存,地下地質(zhì)儲和傳輸管線存儲。然而,當(dāng)作一項存儲技術(shù),以用來探討這項研究,常規(guī)壓力容器技術(shù)的用簡單,方便??紤]到適量儲氫。在一項施工工程,投資方要求設(shè)計一個完整風(fēng)-氫系統(tǒng)。各種額費用,諸如交通,發(fā)牌、及管道。因此,本文概述所做出的假設(shè)都是根據(jù)的,在這項研究中概述了主要的考慮因素,突出設(shè)計特色—水力發(fā)電塔,介紹了幾個設(shè)計概念,并
51、在可行性概念基礎(chǔ)上進(jìn)行比較,比較水塔及壓力容器。</p><p><b> 2 基準(zhǔn)及假設(shè)</b></p><p><b> 2.1氫氣發(fā)電</b></p><p> 這項研究假設(shè)電解槽產(chǎn)生水力發(fā)電的能量儲存在氫塔。于上述表示的那樣,這項研究假質(zhì)子交換膜和高壓力堿性電解槽,可以生產(chǎn)氫氣,在這個壓力基礎(chǔ)上,而無需使用額
52、外的壓縮機</p><p><b> 2.2常規(guī)塔</b></p><p> 我們選擇使用1.5兆瓦塔模型,設(shè)計和研究風(fēng)力發(fā)電機組,為我國基線常規(guī)塔做一個設(shè)計雛形。此塔是模仿常規(guī)塔建成4個錐形,管狀,鋼型材是拴在一起。常規(guī)塔焊接在一起成柱型路段軋制鋼板。一般步驟塔遞減。壁厚逐漸生成線性方式依次遞減向上。該模型假設(shè)恒定塔直徑/壁厚(d/t)的比率為320。為了節(jié)省材
53、料成本的費用,直徑/壁厚是可取的。然而,對于比率高于320,塔受地基牢固的強弱的問題。額外的假設(shè),對于塔,直徑受頂部制約,以應(yīng)至少有1/2的基地直徑,鋼材料用來加工,在樓面的墻壁有一個收益率,強度為350兆帕斯卡。</p><p><b> 2.3常規(guī)壓力容器</b></p><p> 工業(yè)壓力容器的材料和碳素鋼相似,所用的風(fēng)力發(fā)電機組運轉(zhuǎn)。設(shè)以最符合經(jīng)濟(jì)效益,容
54、器幾何外表仍然很高大,如果像海運的話,船只經(jīng)常是受航運的限制,設(shè)備要求實際長度約25m這種長度的限制,才可以在海上運輸,而大多數(shù)都是設(shè)計25米長度,因為這是正規(guī)設(shè)計高度因此,隨之而來的是額外的費用,所以必須降低成本,每公斤的儲存瓦斯,以及高壓力都需額外的壓縮成本。</p><p> 在本文,存儲設(shè)備是有準(zhǔn)確設(shè)計費用的,對于成本/質(zhì)量比。這個比例的費用(以美元計),存裝置除以大量的實物交換氫。荷蘭的正常運行的儲存
55、設(shè)施。在壓力容器,一定量的氣體,隨緩沖作用。以提供所需的加壓提取剩余氣。在某些情況下,如地下儲氣庫時,其氣體無法進(jìn)入的,可以計算成本儲存氣態(tài)氫,相對于其他存儲成本。此外,這一研究模式氫作為一種理煤氣。</p><p><b> 3 氫塔的考慮</b></p><p> 貯氫創(chuàng)造了多項額外的工業(yè)耗損,部分風(fēng)力發(fā)電機塔設(shè)計,加速脆化可能帶來不利的影塔的固然屬性有延展性
56、,屈服強度和疲勞壽命。此外,儲存的氣體水力發(fā)電時,在設(shè)計壓力增加對流層的個數(shù)。因此,地基加固將成為關(guān)鍵性,以用來評測內(nèi)部壓力對塔的設(shè)計壽命。</p><p><b> 3.1腐蝕</b></p><p> 發(fā)生氫脆內(nèi)部的氫塔。常規(guī)風(fēng)力發(fā)電機組的塔保護(hù),在內(nèi)部和外部,當(dāng)一個塔儲存加壓氣體,必須有足夠的耐腐蝕材料。電化學(xué)腐蝕是金屬與電解質(zhì)溶液發(fā)生電化學(xué)作用而引起的破壞
57、。反應(yīng)過程同時有陽極失去電子、陰極獲得電子以及電子的流動(電流),其歷程服從電化學(xué)的基本規(guī)律。金屬在大氣、海水、,工業(yè)用水、各種酸、堿、鹽溶液中發(fā)生的腐蝕都屬于電化學(xué)腐蝕。內(nèi)部的氫氣塔是一個氫從質(zhì)子交換膜電解槽電解分離出來的,不含有污染物,侵蝕(首要是二氧化硫和氯氣)。像水汽,它可以曬干,以低于臨界濕度,一級(不少于80 %相對濕度),大氣腐蝕會滲透。鋼的表面腐蝕裕度小于0.01米/每年。 3.2儲氫攻擊 在高溫高壓下,鋼中的
58、碳同滲入的氫原子反應(yīng)生成甲烷,生成的甲烷又無法擴(kuò)散到鋼的外表面,主要集聚在金屬的晶間處,最終形成高的局部壓力,使金屬開裂和鼓泡。氫的腐蝕過程既可能發(fā)生在金屬表面,也可以發(fā)生在金屬內(nèi)部(主要沿晶界)。隨著溫度和壓力的提高,氫對鋼的腐蝕作用增強,無論是高壓甲醇合成反應(yīng)器還是低壓合成反應(yīng)器,都有氫腐蝕存在。3.3汽蝕</p><p> 汽蝕是普遍用于描述氫環(huán)境脆化的現(xiàn)象, 內(nèi)部汽蝕是造成金屬氫豐富的環(huán)境。氫是產(chǎn)生內(nèi)
59、金屬的結(jié)構(gòu), 通常用來加工和生產(chǎn), 汽蝕是一個過程,其中的氫原子吸附到金屬的表面造成脆性破壞。 渦輪塔構(gòu)成環(huán)境包括溫度,壓力及體積,以及材料性能包括剛度,硬度,強度。 本 節(jié)探討如何發(fā)生汽蝕,在常壓溫度。像放有甲醇的渦輪塔裝置中,再沸器不銹鋼管子的損壞通常是由于管束外壁的實際溫度大大超過溶液的沸騰溫度,使管束表面的液體在極短時間內(nèi)爆沸氣化,產(chǎn)生氣泡,隨著氣泡內(nèi)壓的增加,氣泡破裂。由于氣泡破裂對金屬表面起強烈的錘擊作用,不僅能破壞
60、表面膜,而且可能損壞表面膜下的金屬,促進(jìn)金屬的腐蝕。在熱鉀堿溶液中,由于膜完整與被破壞處的金屬電位相差較大,因此可以形成膜-孔腐蝕電池。通常像氫攻擊將會實施更加越來越大的壓力。試驗數(shù)據(jù)會顯示氫氣表示一定程度的脆化,這意味著設(shè)計渦輪塔相對低氣壓貯藏可能有助于防止氫脆。因此,這種儲存的壓力下考慮,只有約10 %的氫氣管線運行壓力。氫氣純度是另一個考慮的因素,實驗證據(jù)表明,裂紋擴(kuò)展,在強調(diào)標(biāo)本可控制,所引進(jìn)的氧氣進(jìn)入氫氣環(huán)境, 調(diào)查
61、表明,在純氫氣環(huán)境下可以引進(jìn)少200 p</p><p><b> 3.4結(jié)構(gòu)分析</b></p><p> 風(fēng)力渦輪塔內(nèi)部有獨特的結(jié)構(gòu),加壓塔不能經(jīng)受住負(fù)載所造成的振動能量,管狀塔現(xiàn)代效用規(guī)模的風(fēng)力渦輪機通常是有限的,由疲勞強度產(chǎn)生的裂紋在橫向焊縫,這些最為重要。此外,氫壓負(fù)荷不得超過允許壓力容器的標(biāo)準(zhǔn)。風(fēng)力渦輪機都受到不相同的風(fēng)力誘導(dǎo)載荷。這些載荷造成拉伸和壓
62、縮應(yīng)力以及塔的軸向應(yīng)力不均。造成塔的壽命降低薄壁圓筒中各點的第一曲率半徑和第二曲率半徑分別是承受氣體內(nèi)壓的回轉(zhuǎn)薄殼,回轉(zhuǎn)薄殼僅受氣體內(nèi)壓作用時,各處的壓力相等,壓力產(chǎn)生的軸向力V為</p><p><b> V= </b></p><p><b> 即</b></p><p> 薄壁圓筒中,周向應(yīng)力是軸向應(yīng)力的
63、2倍。</p><p><b> 3.5疲勞載荷</b></p><p> 壓力容器在交變載荷的作用下,經(jīng)過一定周期發(fā)生的斷裂,稱為疲勞失效。垂直裂紋主要是拉應(yīng)力造成的,一般的渦輪水塔,疲勞失效一般發(fā)生在容器的軸向方向。疲勞斷裂一般有裂紋萌生、擴(kuò)展和最后斷裂三個階段、疲勞載荷可以分解成平均應(yīng)力和應(yīng)力副,平均應(yīng)力在很大程度上決定疲勞壽命,由于交變應(yīng)力副,運用平均拉伸
64、壓力會增加最大拉應(yīng)力,加速裂紋擴(kuò)展,并縮短疲勞壽命。</p><p> 純力學(xué)性質(zhì)的疲勞,應(yīng)力值低于屈服點經(jīng)過許多周期后才發(fā)生破壞。如果工作應(yīng)力不超過臨界環(huán)應(yīng)力值(疲勞極限)就不會發(fā)生疲勞破壞,而腐蝕疲勞并不存在疲勞極限,往往在很低的應(yīng)力條件下亦會產(chǎn)生斷裂。</p><p><b> 3.6交叉壓力</b></p><p> 由于隨著壓力
65、的上升而儲氫量增加,但主要失敗是是因為容器的疲勞斷裂,一旦這種“交叉壓力”達(dá)到小于或等于臨界壓力水平時,所需的墻體厚度,是由最大允許拉應(yīng)力造成的,而不是軸向應(yīng)力,所以有的工程設(shè)計都規(guī)定厚度作為一個隨著厚度變化,產(chǎn)生疲勞載荷大小的一個函數(shù),交叉壓力,傳統(tǒng)強度設(shè)計準(zhǔn)則假設(shè)材料是無缺陷的均勻連續(xù)體,因而難以解釋脆性斷裂現(xiàn)象。脆性斷裂屬于斷裂力學(xué)的研究領(lǐng)域。斷裂力學(xué)認(rèn)為材料中存在缺陷,其目的是研究缺陷在載荷和環(huán)境作用下的破壞規(guī)律,建立缺陷集合參
66、數(shù)、材料韌性和結(jié)構(gòu)承載能力之間的定量關(guān)系。在壓力容器中。斷裂力學(xué)的應(yīng)用分兩類: 一類是指導(dǎo)壓力容器的選材和設(shè)計;另一類是在役壓力容器的安全評定,按合乎使用的原則,判斷含缺陷壓力容器能否繼續(xù)使用。由于泄漏是一個受眾多因素,包括安裝,設(shè)計,制造和校驗、運行和維護(hù)等影響的復(fù)雜問題,現(xiàn)有的設(shè)計規(guī)范中有關(guān)密封裝置或連接部件的設(shè)計多數(shù)沒有泄露發(fā)生定量的關(guān)系,而是用強度或(和)剛度失效設(shè)計準(zhǔn)則替代泄露失效設(shè)計準(zhǔn)則,并結(jié)合使用經(jīng)驗,以滿足設(shè)備接頭的
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