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1、<p>  本科畢業(yè)設(shè)計(jì)(外文翻譯)</p><p>  具有非光滑特性的仿生推土機(jī)</p><p>  刮板對(duì)土壤阻力減小的影響</p><p>  Effects of non-smooth characteristics</p><p>  on bionic bulldozer blades in resistance<

2、;/p><p>  reduction against soil</p><p>  Effects of non-smooth characteristics on bionic bulldozer blades in resistance reduction against soil</p><p><b>  Abstract</b><

3、/p><p>  The phenomenon of soil adhesion occurs widely when terrain machines and construction machines work; this adhesion increases their working resistance. Bionics is one of the most effective methods to red

4、uce resistance against soil. Several non-smooth convex form bulldozer blades were tested to study the effects of non-smooth characteristics on resistance reduction against soil. Under the same soil and test conditions, t

5、he draft forces of different non-smooth samples were obtained, and were lower t</p><p>  Author Keywords: Non-smooth characteristics; Bionic bulldozer blades; Resistance reduction</p><p>  Artic

6、le Outline</p><p>  1. Introduction </p><p>  2. Experimental details </p><p>  2.1. The bulldozer blade samples </p><p>  2.2. The tested soil </p><p>  2

7、.3. The equipments and conditions</p><p>  3. Results and discussions </p><p>  3.1. Effects of the number of the non-smooth convexes </p><p>  3.2. Effects of the base diameter of

8、the non-smooth convexes </p><p>  3.3. Effects of the distribution of the non-smooth convex </p><p>  3.4. Effects of the height of the non-smooth convexes </p><p>  3.5. Effects of

9、 experimental times on soil adhesion and forces</p><p>  4. Concluding remarks </p><p>  Acknowledgements </p><p>  References</p><p>  1. Introduction</p><p

10、>  The phenomenon of soil adhesion occurs widely when terrain machines and construction machines work; this adhesion increases their working resistance and energy consumption and decreases their qualities. Many method

11、s, such as materials modification, surface shape design, vibration, lubrication, electric-osmosis and magnetization, were adopted to reduce the soil adhesion force between soil and the surface of soil-engaging components

12、. Some research conducted found that polymeric materials and ename</p><p>  The problem of soil adhesion has been solved in some soil-burrowing animals such as dung beetle, ant, and pangolin. Some research h

13、as shown that some parts of their body surfaces were a kind of geometrical non-smooth structure. The non-smooth structure was one of reasons why soil-burrowing animals do not stick soil. Fig. 1 illustrates the non-s

14、mooth morphology of the head of dung beetle. Based on the research of the principles of the non-smooth surfaces of soil-burrowing animals in anti-adhesion</p><p>  Fig. 1. The non-smooth morphology of the he

15、ad of a dung beetle. </p><p>  View Within Article</p><p>  2. Experimental details</p><p>  2.1. The bulldozer blade samples</p><p>  The sample surfaces were convex-f

16、orm non-smooth surfaces and designed as curved surfaces, not plain ones. Fig. 2 shows a photograph of the bulldozer blade sample. The samples and the small convexes on them were cast together. The small convexes wer

17、e different in the number, base diameter, height, distribution form or distribution position. The non-smooth characteristic differences of the samples were shown in Table 1. The samples were 300 mm long, 150 mm wide

18、, and 150 mm high. The angle of the c</p><p>  Fig. 2. A photograph of a bulldozer blade sample used for tests. </p><p>  View Within Article</p><p>  Table 1. The non-smooth charac

19、teristic differences of the samples </p><p>  Full-size table (10K)</p><p>  View Within Article</p><p>  2.2. The tested soil</p><p>  The tested soil was a kind of bl

20、ack clay from Jilin Province, China. The moisture content was 28.25% (d.b.). The particle size distribution of the tested soil is listed in Table 2.</p><p>  Table 2. The particle size distribution of t

21、he tested soil, liquid limit (WL) and plastic limit (WP)</p><p>  Full-size table (2K)</p><p>  View Within Article</p><p>  2.3. The equipments and conditions</p><p> 

22、 The tests were run in a soil bin at Jilin University (Nanling Campus). The dimensions of the soil bin are 2.5 m long, 0.815 m wide and 0.515 m deep. The soil bin is driven by an electric motor through a gear box. In the

23、 experiment, the tested blade was mounted on a fixed frame structure which was above the soil bin. As the soil bin moved, the tested blade cut the soil. The draft forces were measured through two octagonal ring dynamomet

24、ers mounted between the tested blades and the fixed frame str</p><p>  Fig. 3. The experimental system. </p><p>  View Within Article</p><p>  3. Results and discussions</p>

25、<p>  3.1. Effects of the number of the non-smooth convexes</p><p>  Sample No. 1 (smooth), No. 2 (convex NUMBER=16), No. 3 (convex NUMBER=13) and No. 4 (convex NUMBER=19) were chosen as samples for tes

26、ts. The cut velocity was 0.031 m/s, the cut depth was 15 mm, the cut angle was 46° and the moisture content of the tested soil was 28.25%. The experimental results of the draft forces of the above four samples are s

27、hown in Fig. 4. It was obvious that the draft force of sample No. 3 was the lowest in this group. It was 23.9% lower than that of the smooth one. The dr</p><p>  Fig. 4. Effects of convex numbers on dra

28、ft force. </p><p>  View Within Article</p><p>  3.2. Effects of the base diameter of the non-smooth convexes</p><p>  Sample No. 1 (smooth), No. 2 (convex base DIAMETER=30 mm), No.

29、 5 (convex base DIAMETER=40 mm), No. 6 (convex base DIAMETER=20 mm) were selected as testing samples. The testing conditions were identical to those mentioned above. The mean tested draft forces of the above samples are

30、illustrated in Fig. 5. It shows that the draft force of sample No. 5 was the lowest in this group. It was 32.9% lower than that of the smooth one. The draft force of sample No. 6 was 20% lower than that of the smoot

31、h o</p><p>  Fig. 5. Effects of convex base diameter on draft force. </p><p>  View Within Article</p><p>  3.3. Effects of the distribution of the non-smooth convex</p><

32、p>  Under the same soil and testing conditions, the mean draft forces of sample No. 1 (smooth), No. 2 (convex base DIAMETER=30 mm), No. 7 (convex distribution was uniform, convex base diameter was normal) and No. 8 (c

33、onvex distribution was uniform, convex base DIAMETER=30 mm) were plotted in Fig. 6. It was found that the draft force of sample No. 7 was the lowest in this group. It was 13.9% lower than that of the smooth one. The

34、 draft force of sample No. 8 was 1.1% lower than that of the smooth one.</p><p>  Fig. 6. Effects of convex distribution on draft force. </p><p>  View Within Article</p><p>  3.4.

35、Effects of the height of the non-smooth convexes</p><p>  Effects of non-smooth convex height of samples were investigated under the same soil and testing conditions for sample No. 1 (smooth), No. 2 (convex

36、HEIGHT=4 mm), No. 9 (convex HEIGHT=8 mm) and No. 10 (convex HEIGHT=2 mm) samples. The mean draft forces of the above samples are illustrated in Fig. 7. It was found that the draft force of sample No. 9 was the lowes

37、t in this group. It was 19.3% lower than that of the smooth one. The draft force of sample No. 10 was 12.1% lower than that of the smoot</p><p>  Fig. 7. Effects of convex height on draft force. </p>

38、<p>  View Within Article</p><p>  3.5. Effects of experimental times on soil adhesion and forces</p><p>  Under the same soil and testing conditions as the above, sample Nos. 1 and 7 were

39、conducted eight times. After every experiment was conducted, the surfaces of the tested samples remained the same. The soil adhesion on the surfaces was observed, and the draft forces and the vertical forces were measure

40、d, as shown in Fig. 8 and Fig. 9, respectively. A lot of soil adhered to the surface of sample No. 1, and a minimum amount of soil adhered to the surface of sample No. 7. It was found from Fig. 6 an</p><p> 

41、 Fig. 8. Relationship between draft forces and experimental times for two samples. </p><p>  View Within Article</p><p>  Fig. 9. Relationship between vertical forces and experimental times for

42、two samples. </p><p>  View Within Article</p><p>  4. Concluding remarks</p><p>  The draft forces of the designed samples with non-smooth surface were lower than those of the desi

43、gned sample with smooth surface. It was found that the designed samples with non-smooth surface could reduce draft force in this work, that is, a properly designed non-smooth surface can minimize the cutting resistance o

44、f the curved surface bulldozer blade. </p><p>  The factors affecting the cutting resistance of bionic bulldozer blades included non-smooth convex numbers, convex base diameter, convex distribution and conve

45、x height. The sample with the largest convex base diameter had the smallest draft force.</p><p>  Under the same soil and the testing conditions, there was a lot of soil adhered to the surface of the smooth

46、sample, but the non-smooth sample had little. The draft force and the vertical force of the non-smooth sample were lower than that of the smooth one. The draft force of the smooth sample increased with the experimental t

47、imes increasing, but the draft force of the non-smooth sample varied smoothly.</p><p>  具有非光滑特性的仿生推土機(jī)刮板對(duì)土壤阻力減小的影響</p><p><b>  摘要</b></p><p>  當(dāng)?shù)孛鏅C(jī)械和施工機(jī)械工作時(shí),土壤粘附現(xiàn)象經(jīng)常發(fā)生。這種

48、粘附增加了機(jī)械工作阻力。仿生在減小土壤阻力方面是最有效的方法之一。為了研究非光滑特性在減小土壤阻力方面的影響,幾個(gè)具有非光凸起形式的推土機(jī)刮板已被測(cè)試。在同樣的土壤和測(cè)試條件下,又不同的非光滑樣本產(chǎn)生的比那些光滑樣本的要低。擁有最大的凸起底座直徑的樣本有最小的為切削阻力.了觀察土壤粘附和測(cè)試阻力,我們用光滑和非光滑樣本重復(fù)進(jìn)行了實(shí)驗(yàn)。非光滑樣本的表面粘附的土壤最少,而且根據(jù)光滑性也不同。光滑的樣本在土壤粘附和切削阻力方面也是不同的。&l

49、t;/p><p>  Luquan Ren, Zhiwu Han, Jianjiao Li and Jin Tong作者關(guān)鍵詞:非光滑特性;仿生推土機(jī)刮板;減小阻力 1.文章概要 1 導(dǎo)言 2 實(shí)驗(yàn)細(xì)節(jié) 2.1 推土機(jī)刮板樣本 2.2 測(cè)試土壤 2.3 設(shè)備和條件 3結(jié)果和討論 3.1 非光滑凸起數(shù)量的影響3.2 非光滑凸起底座直徑的影響3.3 非光滑凸起分布的影響3.4 非光滑凸起高度的影響

50、3.5 試驗(yàn)次數(shù)對(duì)于減小土壤粘附和阻力的影響 4 結(jié)束語(yǔ) 鳴謝 參考資料</p><p>  1 導(dǎo)言 當(dāng)?shù)孛鏅C(jī)器和施工機(jī)械工作時(shí),土壤粘附現(xiàn)象經(jīng)常發(fā)生。這種粘附增加了機(jī)械的工作阻力和能源消耗,降低了他們的工作質(zhì)量。為了減少存在于土壤和混合土壤組成表面的土壤粘附力,很多方法,如材料改性,表面形狀設(shè)計(jì),振動(dòng),潤(rùn)滑,電氣滲透和磁化,已被采用。一些已實(shí)施的研究表明,聚合材料和瓷釉衣料有能力減少土壤粘附

51、[ 6 , 12 , 13 , 14和17 ] ,但聚合材料在對(duì)抗土壤阻力方面有著較差的耐磨性?;旌贤寥澜M成的表面形狀在減少土壤粘附和摩擦力方面發(fā)揮了至關(guān)重要的作用。為了減少耕地阻力,一種彗星型帶通道孔的模板已被研發(fā)出來(lái)[ 19 ] 。超聲振動(dòng)和機(jī)械振動(dòng)實(shí)驗(yàn)已被實(shí)施,表明由于振動(dòng)而形成的土壤粘附力和土壤摩擦阻力的減少 [ 16和18 ] 。阿拉亞和川西,謝弗等人報(bào)告說(shuō),被注入位于土壤和混合土壤組成表面的流動(dòng)空氣,水和聚合物水溶液有潤(rùn)滑作

52、用,也減少了混合土壤設(shè)備的切削阻力 1和15 ] 。為減少土壤粘附和滑動(dòng)阻力,電滲法已被采納,但電滲透的長(zhǎng)期接觸時(shí)間要求電滲透法的限制使用[ 2日和3 ] 。韓,張等人,研究了在犁形器具耕作阻力方面磁性所起的作用。他們報(bào)告說(shuō),背面附有永磁的犁鏵比</p><p>  圖1 非光滑形態(tài)率領(lǐng)的蜣螂</p><p>  2 實(shí)驗(yàn)細(xì)節(jié) 2.1 :推土機(jī)刮板樣本 樣本表面是凸起形式的非

53、光滑表面并被設(shè)計(jì)成彎曲表面,并非平整表面。圖2顯示的照片為一個(gè)推土機(jī)刮板樣品。樣本和樣本上的小凸起被鑄造在一起。在數(shù)量,底座直徑,高度,分布形式和分布位置上這些小凸起均是不同的。表1表明了這些樣本的非光滑特性的不同。這些樣品又300毫米長(zhǎng), 150毫米寬, 150毫米高。在推土試驗(yàn)中切割角度為52 °。刮板的彎曲半徑是105.2毫米,厚度為15毫米。 </p><p>  圖 2 一幀用于測(cè)試的推土機(jī)刮

54、板的照片。</p><p><b>  表1</b></p><p>  全尺寸表( 10,000 ) 鑒于在第 2.2 測(cè)試土壤 經(jīng)測(cè)試的土壤是一種從吉林省采得的黑色粘土。水分含量為28.25 % ( d.b. ) 。表2列舉了測(cè)試土壤的粒度大小分布。 表2 測(cè)試土壤的粒度分布,液限(輪候冊(cè))和塑性極限(可濕性粉劑)</p><p

55、>  2.3 設(shè)備和條件 試驗(yàn)是在吉林大學(xué)(南嶺校區(qū))的土壤斌中運(yùn)行的。土壤箱長(zhǎng)2.5米,寬 0.815米和深0.515米。土壤斌是由電動(dòng)機(jī)通過(guò)齒輪箱驅(qū)動(dòng)的。在實(shí)驗(yàn)中,被測(cè)試的刮板安裝在一個(gè)高于土壤斌的固定框架結(jié)構(gòu)上。當(dāng)土壤斌轉(zhuǎn)動(dòng)時(shí),被測(cè)刮板切割土壤。由安裝在被測(cè)刮板和固定框架之間的兩個(gè)八角環(huán)測(cè)功機(jī)測(cè)量切削阻力。這些切削阻力的信號(hào)由一個(gè)拉緊的度量器感測(cè),然后被記錄在磁帶數(shù)據(jù)記錄器中。所記錄的數(shù)據(jù)由一個(gè)信號(hào)處理器加工處理。

56、切割的深度是15毫米,切割速率是0.031米/ s。所有樣本 相同條件下被測(cè)試,每個(gè)實(shí)驗(yàn)重復(fù)3次。圖3展現(xiàn)了實(shí)驗(yàn)系統(tǒng)。</p><p><b>  圖3 實(shí)驗(yàn)系統(tǒng)</b></p><p>  3 結(jié)果和討論 3.1 非光滑凸起數(shù)量的影響 樣本1(光滑) ,樣本 2(凸數(shù)= 16 ) ,樣本 3(凸數(shù)= 13 )和樣本4(凸數(shù)= 19 )作為樣本進(jìn)行測(cè)試。切

57、割速度0.031米/ s,切割深度為15毫米,切割角度為46 °和測(cè)試土壤的水分含量為28.25 % 。圖4表明了上面四個(gè)樣本的切削阻力的實(shí)驗(yàn)結(jié)果。很明顯,這一組中樣本3的切削阻力是最低的。比光滑樣本低了23.9 %。樣本4的切削阻力比光滑樣本低了19.0 %。樣本1最高。</p><p>  圖4 非光滑凸起數(shù)量對(duì)切削阻力的影響</p><p>  3.2非光滑凸起底座直徑的影

58、響樣本號(hào)(光滑) ,樣本 2(= 30毫米) ,樣本5(凸 起底座直徑= 40毫米) ,樣本6(凸起底座直徑= 20毫米)被選定為測(cè)試樣本。測(cè)試條件與上述相同。圖5表明了上述樣本的平均測(cè)試力。這表明,樣本5的切削阻力在這一組中是最低的。壁光滑樣本低了32.9 %。樣本6的切削阻力比光滑樣本低了20 %。樣本1是最高的。</p><p>  圖5 非光滑凸起底座直徑的影響</p>

59、<p>  3.3 非光滑凸起分布的影響</p><p>  在相同的土壤和測(cè)試條件下,樣本1(光滑) ,樣本2(凸起底座直徑= 30毫米)樣本7(凸起分布均勻,凸起底座直徑為正常)和NO 8 (凸起分布均勻,凸起底座直徑 = 30毫米)的平均切削阻力被繪制在圖 6 。結(jié)果發(fā)現(xiàn),在這一組中樣本7的切削阻力是最低的。比光滑樣本低了13.9 % 。樣本8的切削阻力比光滑樣本低了1.1 %。樣本1最高。<

60、;/p><p>  圖6 非光滑凸起分布對(duì)切削阻力的影響</p><p>  3.4 非光滑凸起高度的影響</p><p>  我們用樣品1(光滑) ,樣本2(凸高度= 4毫米) 樣本9(凸高度= 8毫米)和樣本10 (凸高度= 2毫米)來(lái)測(cè)試非光滑凸起高度的影響。圖7表明了上述樣本的平切削阻力均。 結(jié)果發(fā)現(xiàn),在這一組中樣本9的切削阻力最低。比光滑樣本低了19.3 %

61、 。樣本10的切削阻力比光滑樣本低了12.1 %。樣本1是最高的。</p><p>  圖7 非光滑凸起高度對(duì)切削阻力的影響</p><p>  3.5試驗(yàn)次數(shù)對(duì)于土壤粘附和阻力的影響 與上述情況相同的土壤和測(cè)試條件下,,樣品1和7被測(cè)試了 8次。在每次試驗(yàn)實(shí)施之后,測(cè)試樣品的表面保持不變。正如圖 8和圖 9表明的,我們觀察到了表面的土壤粘附,測(cè)量到了切削阻力和垂直力。樣本1的表

62、面附著了很多土壤,樣本7的表面附著的土壤最少?gòu)膱D6和圖7中我們可以發(fā)現(xiàn)樣本7的力切削阻力。由于樣本1表面的土壤附著,隨著實(shí)驗(yàn)次數(shù)的增加切削阻力也增加,表明了累計(jì)附著的現(xiàn)象。然而,由于表面的土壤附著很少,樣本7的切削阻力由光滑性的變化而不同。</p><p>  圖8 切削阻力與兩實(shí)驗(yàn)樣本的關(guān)系</p><p>  圖9 垂直力與兩實(shí)驗(yàn)樣本的關(guān)系</p><p>

63、  4 結(jié)束語(yǔ) 在非光滑表面設(shè)計(jì)樣本的切削阻力比又光滑表面設(shè)計(jì)樣本的低。結(jié)果發(fā)現(xiàn),有非光滑表面的而設(shè)計(jì)樣本可以在工作中減小切削阻力,即妥善設(shè)計(jì)非光滑表面可以縮小推土機(jī)刮板彎曲表面的切割阻力。 影響推土機(jī)刮板切割阻力的因素包括非光滑表面凸起的數(shù)量,凸起底座直徑,凸起分布和凸起高度。擁有最大凸起底座直徑的樣本又最小的切削阻力。在相同的土壤和測(cè)試條件下光滑樣本的表面附著的土壤很多,而非光滑樣本的表面附著的很少。非光滑樣本的

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