康建明 李樹君 楊學(xué)軍,3 劉立晶 王長偉
(1.中國農(nóng)業(yè)機(jī)械化科學(xué)研究院, 北京 100083; 2.新疆農(nóng)墾科學(xué)院機(jī)械裝備研究所, 石河子 832000;3.南方糧油作物協(xié)同創(chuàng)新中心, 長沙 410128; 4.現(xiàn)代農(nóng)裝科技股份有限公司, 北京 100083)
基于多體動(dòng)力學(xué)的圓盤式開溝機(jī)虛擬仿真與功耗測試
康建明1,2李樹君1楊學(xué)軍1,3劉立晶3,4王長偉4
(1.中國農(nóng)業(yè)機(jī)械化科學(xué)研究院, 北京 100083; 2.新疆農(nóng)墾科學(xué)院機(jī)械裝備研究所, 石河子 832000;3.南方糧油作物協(xié)同創(chuàng)新中心, 長沙 410128; 4.現(xiàn)代農(nóng)裝科技股份有限公司, 北京 100083)
目前圓盤式開溝機(jī)功率消耗主要通過理論計(jì)算或樣機(jī)試制后的田間試驗(yàn)等方法得出,測試結(jié)果受環(huán)境、設(shè)備精度影響較大,為此提出了利用虛擬測試平臺(tái)評(píng)估圓盤式開溝機(jī)功率消耗的方法。首先建立圓盤式開溝機(jī)工作部件的ANSYS動(dòng)力學(xué)模型,并進(jìn)行邊界約束條件和載荷設(shè)置,分別模擬圓盤式開溝機(jī)在開溝深度400 mm、前進(jìn)速度0.8 km/h、刀盤轉(zhuǎn)速180 r/min和開溝深度500 mm、前進(jìn)速度1.5 km/h、刀盤轉(zhuǎn)速220 r/min 2種工況下的功率消耗,仿真結(jié)果為31.26 kW和32.67 kW;然后構(gòu)建相同工況的田間功耗測試系統(tǒng),測得的實(shí)際功耗為33.57 kW和35.41 kW,仿真值與實(shí)測值相對誤差分別為6.88%和7.73%,驗(yàn)證了該種測試方法的準(zhǔn)確性和可行性。最后分別選取3種開溝深度、2種前進(jìn)速度和3種刀盤轉(zhuǎn)速因素組成18種開溝工況,對其進(jìn)行仿真分析,結(jié)果表明:刀盤轉(zhuǎn)速在200 r/min時(shí),無論前進(jìn)速度高低,圓盤式開溝機(jī)均具有最低的功耗。
圓盤式開溝機(jī); 虛擬測試; 多體動(dòng)力學(xué); 功耗
開溝施肥是果園栽培生產(chǎn)管理中工作量最大的環(huán)節(jié),目前主要靠人工完成,勞動(dòng)強(qiáng)度大,作業(yè)效率低。開溝機(jī)是一種開挖溝渠的專用機(jī)械,按工作原理不同可分為:鏵式犁開溝機(jī)[1]、圓盤式開溝機(jī)[2]和鏈?zhǔn)介_溝機(jī)[3]。圓盤式開溝機(jī)在工作過程中具有散土均勻、工作效率高等優(yōu)點(diǎn),在果園、葡萄園等農(nóng)業(yè)生產(chǎn)領(lǐng)域得到了廣泛的應(yīng)用。美國、日本的圓盤式開溝機(jī)已形成系列產(chǎn)品,最大功率達(dá)130 kW,可挖深1.8 m、寬2.0 m的溝渠[4]。國內(nèi)對圓盤式開溝機(jī)械開展了相關(guān)研究,蘇子昊等[5]設(shè)計(jì)了開溝施肥機(jī)的定向施肥裝置;葉強(qiáng)等[6]設(shè)計(jì)了一種驅(qū)動(dòng)型葡萄園小型開溝機(jī);朱繼平等[7]對超大型圓盤開溝機(jī)工作時(shí)刀具的運(yùn)動(dòng)軌跡、速度特性進(jìn)行了仿真分析;袁曉明等[8]對大耕深旋耕刀的制造工藝及耐磨性進(jìn)行了研究;盧彩云等[9]運(yùn)用ANSYS/LS_DYNA軟件對平面刀切削土壤過程進(jìn)行有限元分析;齊龍等[10]對松土刀在不同轉(zhuǎn)速下的土壤切削過程進(jìn)行了數(shù)值模擬,并對不同轉(zhuǎn)速下松土刀的阻力和功耗進(jìn)行分析。但對開溝機(jī)械功率性能評(píng)估方面的研究鮮有報(bào)道,例如目前圓盤式開溝機(jī)的功率消耗主要是通過理論計(jì)算[11]、樣機(jī)試制后的田間試驗(yàn)[12]等方式獲得。這些方法均受外界條件限制,測試結(jié)果受環(huán)境、設(shè)備精度的影響較大。
隨著計(jì)算機(jī)技術(shù)的發(fā)展以及土壤本構(gòu)模型的日益完善,有限元方法成為分析農(nóng)機(jī)具觸土部件和土壤相互作用規(guī)律的有效工具[13]。本文以課題組研制的圓盤式開溝機(jī)為研究對象,基于多體動(dòng)力學(xué)理論,構(gòu)建ANSYS軟件平臺(tái)下的圓盤式開溝機(jī)功耗測試仿真模型,并與田間試驗(yàn)數(shù)據(jù)對比驗(yàn)證,為農(nóng)機(jī)產(chǎn)品在設(shè)計(jì)階段的性能評(píng)估提供一種新的方法。
1.1 開溝刀盤有限元模型
由于圓盤式開溝機(jī)模型較為復(fù)雜,考慮到建模及仿真運(yùn)行耗時(shí)長等問題,以課題組研制的圓盤式開溝機(jī)為研究對象時(shí),對其結(jié)構(gòu)部件進(jìn)行簡化:在開溝刀盤上直接加載經(jīng)傳動(dòng)比計(jì)算后的轉(zhuǎn)速和前進(jìn)速度,簡化傳動(dòng)總成和牽引裝置;忽略殼體等對功耗影響較小的部件;省去占次要地位的倒角、圓角和螺栓連接等特征,利用Solidworks軟件建立開溝刀盤實(shí)體模型,將模型導(dǎo)入ANSYS前處理界面中,對開溝刀盤采用拉格朗日算法進(jìn)行網(wǎng)格劃分。其主要參數(shù)為:密度0.007 85 g/mm3,彈性模量2.06 MPa,泊松比0.26[14-15]。
1.2 土壤模型
針對華北地區(qū)黃壤土的特性,土壤材料采用LS-DYNA中的MAT147(MAT_FHWA_SOIL)土壤材料模型,輸入特定的參數(shù),MAT_FHWA_SOIL采用修正的Mohr-Coulomb屈服準(zhǔn)則[16],其應(yīng)力不變量等式表示為
(1)
其中
(2)
式中 f——壓力,Nφ——內(nèi)摩擦角,(°)J2——偏應(yīng)力的第2不變量θ——偏應(yīng)力面中的極角,(°)K(θ)——應(yīng)力羅德角函數(shù)A——屈服面準(zhǔn)則與標(biāo)準(zhǔn)M-C屈服面之間的相似因數(shù)
c——黏聚力,MPa
黃壤土模型[17-18]的主要參數(shù)取值如表1所示,其余參數(shù)參考LS-DYNA971中MAT147默認(rèn)值,采用g-mm-ms-N-MPa單位制。
表1 黃壤土材料參數(shù)
Tab.1 Parameters of yellow loam
參數(shù) 數(shù)值參數(shù) 數(shù)值土壤種類黃壤土剪切模量/MPa21土壤密度/(g·cm-3)2.59黏聚力/MPa0.02土粒密度/(g·cm-3)2.79內(nèi)摩擦角/(°)32.5體積模量/MPa28含水率/%24.3
1.3 土壤-開溝刀盤模型
在建立土壤-開溝刀盤模型時(shí),考慮開溝刀盤切削方式及邊界條件處理要求,土壤仿真模型設(shè)定為簡單的長方體,其尺寸為800 mm×500 mm×500 mm,土壤模型通過映射網(wǎng)格劃分成六面體網(wǎng)格,根據(jù)開溝深度要求,土壤模型高度大于500 mm。為限制土壤切削模擬的總網(wǎng)格數(shù)量,本文將土壤網(wǎng)格略微粗大化,但土壤網(wǎng)格尺寸小于刀片網(wǎng)格尺寸,避免模擬過程中出現(xiàn)穿刺現(xiàn)象。圖1為土壤和開溝刀盤在ANSYS軟件中的初始模型。
圖1 土壤-開溝刀盤初始模型Fig.1 Initial position model of soil-blade
1.4 邊界約束條件與施加載荷
為了盡可能模擬圓盤式開溝機(jī)的工作狀況,根據(jù)開溝刀盤轉(zhuǎn)速確定旋轉(zhuǎn)一周的時(shí)間步長,由于圓盤式開溝機(jī)開溝刀盤轉(zhuǎn)速一般在220 r/min以內(nèi),故設(shè)置0.27 s為分析步長。模型中的土壤底面完全固定,對側(cè)面采用對稱邊界條件定義,模擬土壤真實(shí)環(huán)境,保證側(cè)面?zhèn)认虿粫?huì)有位移。模型中的開溝刀盤除前進(jìn)方向和旋轉(zhuǎn)方向外都對其進(jìn)行完全約束。以上所有運(yùn)動(dòng)均采用速度加載,對以上運(yùn)動(dòng)狀態(tài)加載預(yù)定義場,并設(shè)置光滑幅值曲線,對整個(gè)模型考慮重力作用,施加重力加速度-9 800 mm/s2,定義開溝刀盤與土壤表面的接觸屬性切向行為為罰函數(shù),摩擦因數(shù)0.3,并采用有限滑移,法向?yàn)橛步佑|。
圖2 開溝刀盤與土壤切削過程仿真結(jié)果Fig.2 Group pictures of cutting process
應(yīng)用ANSYS/LS-DYNY軟件,采用時(shí)間分差法對時(shí)間進(jìn)行動(dòng)力學(xué)顯式積分,設(shè)置2種工作狀態(tài)。工況1:前進(jìn)速度0.8 km/h,開溝深度400 mm,刀盤轉(zhuǎn)速180 r/min;工況2:前進(jìn)速度1.5 km/h,開溝深度500 mm,刀盤轉(zhuǎn)速220 r/min。由于ANSYS/LS-DYNY軟件計(jì)算生成的數(shù)據(jù)并不能夠完全被LS-DYNA971軟件所接受,故需首先在ANSYS中生成相應(yīng)的K文件,對K文件內(nèi)容適當(dāng)修改后再遞交給LS-DYNA971軟件求解,進(jìn)而對開溝過程進(jìn)行仿真研究。
2.1 開溝機(jī)理分析
開溝刀盤以工況1設(shè)置參數(shù)從左向右逆時(shí)針切削土壤,如圖2所示(由于2種工況下的開溝機(jī)理相同,故本節(jié)以工況1為例進(jìn)行闡述)。隨著開溝刀盤轉(zhuǎn)動(dòng),開溝刀頂端首先與土壤發(fā)生接觸(圖2a),開溝刀的內(nèi)側(cè)面開始向斜上方擠壓土壤(圖2b和圖2c),受到擠壓的土壤發(fā)生變形,當(dāng)變形量足夠大時(shí),土壤被撕裂,在開溝刀的切削下,土壤在沿開溝刀前進(jìn)方向最先被切割開來(圖2d);隨后,土壤在受到開溝刀內(nèi)側(cè)面擠壓和刃口切削的雙重作用下迅速破壞(圖2e和圖2f),并被拋至溝外。從圖2e可以看出,被開溝刀切下的土壤有沿向上運(yùn)動(dòng)的趨勢,證明了開溝刀在實(shí)際作業(yè)中對土壤有縱向推送作用。當(dāng)切削仿真運(yùn)行至32.4 ms 時(shí),相鄰的開溝刀開始入土,受土壤模型限制,開溝刀并沒有掃過整個(gè)切削區(qū)間,但仍然可以看出前1把開溝刀的尾端未越過土壤正上方時(shí),后1把開溝刀已經(jīng)與土壤接觸,表明相鄰開溝刀有重疊切土?xí)r段,切削過程較平穩(wěn)。
2.2 開溝過程功耗分析
利用LS-DYNA971軟件可視化后處理模塊,對開溝過程功率消耗進(jìn)行分析,如圖3所示。在開溝刀與土壤相互作用初期,工況1和工況2的功率消耗都隨時(shí)間不斷增加而迅速增大,這主要是因?yàn)橥寥朗軘D壓變形至破碎需要消耗大量能量;另一方面,開溝深度越大,土壤的堅(jiān)實(shí)度越大,刀片的切削力使土壤的變形也就越來越大,總功耗變化速率較快,工況1在0~15.44 ms過程中,開溝功耗從0迅速上升至33.68 kW,當(dāng)仿真運(yùn)行至23.16 ms時(shí),開溝功耗達(dá)到最大值35.26 kW,隨著開溝過程的進(jìn)行,功耗變化趨于穩(wěn)定值31.26 kW;工況2在0~15.44 ms過程中,開溝功耗從0上升至36.68 kW,當(dāng)仿真運(yùn)行至23.16 ms時(shí),開溝功耗達(dá)到最大值37.26 kW,隨著開溝的進(jìn)行,功耗變化趨于穩(wěn)定值32.67 kW,這是由于土壤顆粒在被破壞后相互之間的結(jié)合力減小,切削力維持在一個(gè)穩(wěn)定的狀態(tài),開溝功耗最終維持在一個(gè)穩(wěn)定值附近。
圖3 開溝過程作業(yè)功耗曲線Fig.3 Power consumption curves of ditch process
2.3 田間試驗(yàn)測試及仿真結(jié)果對比
2.3.1 試驗(yàn)設(shè)備與條件
圖4 測試裝置圖Fig.4 Pictures of test device
為驗(yàn)證仿真模型的準(zhǔn)確性,開發(fā)了圓盤式開溝機(jī)田間功耗測試系統(tǒng),測試裝置原理圖如圖4所示。試驗(yàn)設(shè)備包括:東方紅504型拖拉機(jī),圓盤式開溝機(jī)、12 V直流電源、AKC-205B型扭矩傳感器(精度±0.1%,量程0~1 500 N·m)以及數(shù)據(jù)采集卡(分辨率12 Bit,采集頻率0~100 kHz)、數(shù)據(jù)處理終端等。試驗(yàn)地點(diǎn)為:北京市通州區(qū)澳香園農(nóng)業(yè)科技園,土壤平均堅(jiān)實(shí)度調(diào)整為0.29 MPa,土壤含水率為16.2%。
2.3.2 試驗(yàn)因素與性能指標(biāo)
試驗(yàn)時(shí)選用工況1和工況2設(shè)定的工作參數(shù)值,根據(jù)理論力學(xué)原理可知,開溝刀盤扭矩的變化即可反映功率消耗的差異,開溝過程的功率消耗[19]為
(3)
式中 P——開溝過程的功率消耗,kWn——開溝刀盤轉(zhuǎn)速,r/minM——開溝刀盤扭矩,N·m
因此,在開溝過程中只要測得動(dòng)力輸出軸上的轉(zhuǎn)矩和轉(zhuǎn)速,乘以傳遞效率,即可計(jì)算出開溝過程中的功率消耗。試驗(yàn)借助于扭矩、轉(zhuǎn)速測量儀和傳感器組成的測試系統(tǒng)來測量作業(yè)過程中的扭矩和轉(zhuǎn)速,實(shí)時(shí)記錄功耗數(shù)據(jù)。
試驗(yàn)時(shí),在2種工況下每隔2m取1個(gè)測試點(diǎn),共取10個(gè),測試數(shù)據(jù)如表2所示。經(jīng)計(jì)算工況1的平均功率消耗為33.57kW,仿真結(jié)果(31.26kW)與其相比,誤差為6.88%,工況2的平均功率消耗為35.41kW,仿真結(jié)果(32.67kW)與其相比,誤差為7.73%,驗(yàn)證了該種測試方法的準(zhǔn)確性和可行性。
表2 不同測試點(diǎn)功率消耗
Tab.2 Power consumption values at different time
序號(hào)工況1工況2扭矩/(N·m)功耗/kW扭矩/(N·m)功耗/kW11659.031.271531.535.2821832.534.541500.734.5731868.635.221617.037.2541682.431.711537.135.4152041.038.471507.634.7361860.735.071581.436.4371672.331.521450.333.4181707.932.191584.936.5191818.734.281574.936.28101665.431.391486.334.24均值1780.933.571537.235.41
為進(jìn)一步研究圓盤式開溝機(jī)前進(jìn)速度、開溝深度和刀盤轉(zhuǎn)速對功率消耗的影響,根據(jù)果園開溝施肥深度在300~500 mm的農(nóng)藝要求,確定仿真試驗(yàn)時(shí)開溝深度為300、400、500 mm;前進(jìn)速度小于1.0 km/h生產(chǎn)率達(dá)不到設(shè)計(jì)要求,大于1.5 km/h時(shí)開溝深度不穩(wěn)定,結(jié)合拖拉機(jī)擋位,確定前進(jìn)速度為1.0 km/h和1.5 km/h;根據(jù)文獻(xiàn)[20]及前期預(yù)試驗(yàn),確定刀盤轉(zhuǎn)速為180、200、220 r/min,設(shè)計(jì)了3種因素下的18種工況分析,仿真試驗(yàn)安排及結(jié)果如表3所示。
由表3可知,在開溝深度一定時(shí),刀盤轉(zhuǎn)速越大,功率消耗越大,轉(zhuǎn)速變化與功率消耗存在著遞增的線性關(guān)系,其中開溝深度300 mm并在高速前進(jìn)下,刀盤轉(zhuǎn)速為200 r/min時(shí),功率消耗最低。在開溝深度為300 mm和400 mm時(shí),前進(jìn)速度越高,功率消耗越大,但在開溝較深的500 mm工況下,1.5 km/h的前進(jìn)速度使得功率消耗在200 r/min工況下發(fā)生突降。在300 mm和500 mm開溝深度下,200 r/min的刀盤轉(zhuǎn)速在2種前進(jìn)速度中功率消耗最低,當(dāng)開溝深度為500 mm時(shí),功率消耗最小出現(xiàn)在刀盤轉(zhuǎn)速為200 r/min、前進(jìn)速度1.5 km/h的情況下,值得注意的是,雖然在1.0 km/h、200 r/min的工況下,功率消耗發(fā)生了激增,但在200 r/min工況下仍然具有低功耗的特性,此時(shí)圓盤式開溝機(jī)仍可以高速前進(jìn)。因此,無論開溝深淺,刀盤轉(zhuǎn)速200 r/min為圓盤式開溝機(jī)高速或低速前進(jìn)下的最優(yōu)轉(zhuǎn)速。
表3 各因素時(shí)的功率消耗
Tab.3 Power consumption of various factors
開溝深度/mm前進(jìn)速度/(km·h-1)刀盤轉(zhuǎn)速/(r·min-1)功耗/kW18033.51.020033.230022037.518034.21.520033.822036.418035.01.020034.840022027.618036.41.520036.622039.318037.61.020041.850022038.518037.21.520036.922039.4
4.1 試驗(yàn)方案及結(jié)果
為驗(yàn)證上述結(jié)論,本次試驗(yàn)將目前圓盤式開溝機(jī)大多采用的刀盤轉(zhuǎn)速220 r/min[21]與本研究結(jié)果200 r/min進(jìn)行功耗對比試驗(yàn),試驗(yàn)方案及結(jié)果如表4所示。
4.2 結(jié)果分析
由表4可知,作業(yè)功耗的試驗(yàn)值略高于理論值,這是由于土壤含水率、作業(yè)過程中不可避免的摩擦及磨損而導(dǎo)致額外功率消耗,開溝深度500 mm時(shí),功率消耗最高可降低8.5 kW;開溝深度400 mm時(shí),功率消耗最高可降低9.6 kW;開溝深度300 mm時(shí),功率消耗最高可降低4.6 kW。由此可見,開溝深度越大,刀盤轉(zhuǎn)速在200 r/min時(shí)的功率消耗減小越明顯。
表4 不同轉(zhuǎn)速下功耗對比試驗(yàn)結(jié)果
Tab.4 Power consumption contrast test result at different rotary speeds
開溝深度/mm前進(jìn)速度/(km·h-1)刀盤轉(zhuǎn)速/(r·min-1)功耗/kW1.020035.630022039.41.520036.422041.01.020036.940022044.61.520037.222046.81.020043.250022051.41.520044.522053.0
(1)通過理論分析,建立圓盤式開溝機(jī)動(dòng)力學(xué)虛擬功耗測試平臺(tái),在開溝深度為400 mm、前進(jìn)速度為0.8 km/h、刀盤轉(zhuǎn)速為180 r/min工況下,功耗仿真值為31.26 kW;在開溝深度為500 mm、前進(jìn)速度為1.5 km/h、刀盤轉(zhuǎn)速為220 r/min工況下,功耗仿真值為32.67 kW,田間功耗仿真值與實(shí)測值誤差分別為6.88%和7.73%,驗(yàn)證了圓盤式開溝機(jī)虛擬功耗測試平臺(tái)的準(zhǔn)確性。
(2)開展了圓盤式開溝機(jī)開溝深度、前進(jìn)速度以及刀盤轉(zhuǎn)速3因素下的18種工況仿真分析,由仿真結(jié)果得知:開溝深度一定時(shí),圓盤式開溝機(jī)功率消耗分別與前進(jìn)速度、刀盤轉(zhuǎn)速呈線性遞增關(guān)系;在開土深度和前進(jìn)速度一定時(shí),可以認(rèn)為200 r/min在3種轉(zhuǎn)速中功率消耗最低。
(3)在不同開溝深度和不同前進(jìn)速度下,對功耗最低的刀盤轉(zhuǎn)速200 r/min和目前普遍采用的220 r/min進(jìn)行開溝功耗對比試驗(yàn),結(jié)果表明,在開溝深度500、400、300 mm時(shí),刀盤轉(zhuǎn)速200 r/min比220 r/min節(jié)省功耗8.5、9.6、4.6 kW,開溝深度越大,刀盤轉(zhuǎn)速在200 r/min時(shí)的功率消耗減小程度越明顯。
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Virtual Simulation and Power Test of Disc Type Ditcher Based on Multi-body Dynamics
KANG Jianming1,2LI Shujun1YANG Xuejun1,3LIU Lijing3,4WANG Changwei4
(1.ChineseAcademyofAgriculturalMechanizationSciences,Beijing100083,China2.MechanicalEquipmentResearchInstitute,XinjiangAcademyofAgriculturalandReclamationScience,Shihezi832000,China3.CollaborativeInnovationCenterforSouthernGrainandOilCrop,Changsha410128,China
4.ModernAgriculturalEquipmentCo.,Ltd.,Beijing100083,China)
Aiming at the problem of that the power consumption of disc type ditcher is difficult to test, a virtual test platform evaluation disc type ditcher set power consumption method was proposed. Firstly, the dynamics model of disc type ditcher was established. In order to shorten the operation time, the secondary characteristics such as chamfer, fillet and connection were omitted. The boundary conditions and loads were set up. The virtual simulation of power consumption in disc type ditcher was carried out with trenching depths of 400 mm and 500 mm, forward speeds of 0.8 km/h and 1.5 km/h, rotation speeds of 180 r/min and 220 r/min, respectively. The power curve of ditch process showed that at the beginning of soil cutting, power consumption was increased quickly, the reason for which was a great deal of power consumption was needed during the process of soil deformation and broken. After that the power consumption was tended to be stable, for the reason of which was the binding force was tended to be less after the soil particle was destroyed. Then the field power test system was built and the relative errors were 6.88% and 7.73%, respectively, compared with simulation results. The accuracy and feasibility of the proposed method were verified. Finally, totally 18 conditions (three trenching depths, two forward speeds, and three rotating speeds) were selected to carry out the simulation. The results showed that with a certain trenching depth, the disc type ditcher had an increasing linear relationship with forward speed and rotation speed. With a certain ditching depth and forward speed, the lowest power consumption was appeared at rotation speed of 200 r/min. Moreover, with a large trenching depth and forward speed, the effect of rotation speed on power consumption was obvious. When the rotary speed was 200 r/min,both low and high speeds, disc type ditcher had the lowest power consumption value. According to comparison at rotary speed of 219 r/min in different ditching depths and forward speeds, the power consumption at rotary speed of 200 r/min was decreased by 8.5 kW, 9.6 kW and 4.6 kW, the results provided a theoretical basis for power consumption measurement of rotary ditcher.
disc type ditcher; virtual test; multi-body dynamics; power consumption
10.6041/j.issn.1000-1298.2017.01.008
2016-05-19
2016-06-21
國家國際科技合作專項(xiàng)(2013DFA71130)和北京市科技計(jì)劃項(xiàng)目(D151100003715003)
康建明(1984—),男,博士生,新疆農(nóng)墾科學(xué)院助理研究員,主要從事農(nóng)業(yè)機(jī)械裝備及關(guān)鍵技術(shù)研究,E-mail: kjm531@sina.com
劉立晶(1976—),女,研究員,博士生導(dǎo)師,主要從事農(nóng)業(yè)機(jī)械裝備及關(guān)鍵技術(shù)研究,E-mail: xylijj@sina.com
S222.3
A
1000-1298(2017)01-0057-07