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雙極荷電凝并降低柴油機顆粒排放數(shù)量的試驗研究

2017-11-24 06:08:33劉軍恒平垚萬峰
農(nóng)業(yè)工程學報 2017年14期
關鍵詞:荷電柴油機排氣

孟 建,劉軍恒,孫 平垚,萬峰,范 義

(1. 江蘇大學汽車與交通工程學院,鎮(zhèn)江 212013;2. 山東理工大學交通與車輛工程學院,淄博 255049)

雙極荷電凝并降低柴油機顆粒排放數(shù)量的試驗研究

孟 建1,2,劉軍恒1※,孫 平1垚,萬峰1,范 義1

(1. 江蘇大學汽車與交通工程學院,鎮(zhèn)江 212013;2. 山東理工大學交通與車輛工程學院,淄博 255049)

針對柴油機排氣顆粒粒徑小、數(shù)量濃度高難以控制的問題,以共軌柴油機排氣顆粒為研究對象,采用自制的荷電凝并試驗臺,研究了在1 600和2 600 r/min轉速下,荷電電壓(0、5、10、15、20 kV)對排氣顆粒數(shù)量濃度分布、質(zhì)量密度分布、質(zhì)量中位徑、總數(shù)量濃度和柴油機顆粒捕集器(diesel particulate filter,DPF)捕集效率等的影響。試驗結果表明,雙極荷電凝并能夠降低柴油機排氣顆粒的總數(shù)量濃度,核模態(tài)顆粒(5~50 nm)和小于93.1 nm積聚態(tài)顆粒(50~500 nm)數(shù)量濃度降低,大于93.1 nm的積聚態(tài)顆粒數(shù)量濃度略有升高。隨著荷電電壓的升高,2種轉速下(最大扭矩轉速1 600 r/min和額定轉速2 600 r/min),25%負荷、50%負荷和75%負荷時,45.3~80.6 nm峰值處顆粒數(shù)量濃度隨荷電電壓的升高降幅明顯,100%負荷時,8.06~12.4 nm峰值處顆粒數(shù)量濃度降幅明顯高于45.3~80.6 nm峰值處;顆粒質(zhì)量濃度峰值向大粒徑方向偏移,質(zhì)量中位徑范圍由96~101 nm增大至102~110 nm。雙極荷電凝并能夠提高DPF的捕集效率,降低柴油機排氣顆粒的數(shù)量和質(zhì)量排放,50%負荷時,10 kV下的DPF的捕集效率較0 kV提高了9個百分點。該研究可為雙極荷電凝并技術的車用提供參考。

柴油機;排放控制;顆粒物;雙極荷電;顆粒數(shù)量濃度;捕集效率

0 引 言

柴油機排氣顆粒是大氣顆粒物的主要來源之一,大部分顆粒粒徑小于100 nm[1-3],不易沉降,造成環(huán)境污染并危害人體健康[4-5],最新研究表明小于100 nm的顆粒能輕易穿透人體細胞壁進入血液與大腦,甚至能導致某些遺傳性疾[6],因此,控制柴油機顆粒排放尤其是小粒徑顆粒排放具有重要的意義。近年來世界各國越來越重視柴油機顆粒排放數(shù)量,歐Ⅴ和歐Ⅵ排放法規(guī)中增加了針對顆粒排放數(shù)量的限值要求[7]。柴油機顆粒捕集器(diesel particulate filter,DPF)是目前公認降低柴油機顆粒排放最有效的手段,廣泛應用于車用柴油機[8-10],但 DPF對于超細顆粒的捕集效率較低[11-14]。 降低DPF載體孔隙粒徑,能夠提高捕集效率,但會造成DPF壓降增大,導致柴油機燃燒惡化;在不改變DPF過濾體結構參數(shù)的情況下,增大排氣顆粒粒徑,能夠有效提高捕集效率[11]。

雙極荷電凝并能夠提高顆粒間的碰撞概率,增大凝并系數(shù)[15],使帶電顆粒更易于凝并成較大顆粒,促進顆粒粒徑增長,該技術長期以來一直被國內(nèi)外學者重視,并在電場除塵領域取得了很好的效果[16-19]。Eliasson等[16]通過試驗研究了異極性荷電粉塵的凝并效率,發(fā)現(xiàn)在對稱偶極荷電時,亞微米顆粒靜電凝并速率較中性顆粒熱凝并速率高102~104倍。Koizumi等[17]計算了外電場作用下雙極性荷電顆粒的凝并系數(shù),而亞微米顆粒異極性荷電后在非對稱狀態(tài)下較對稱時凝并效果好,但是隨著凝并的進行大多數(shù)新生成顆粒帶電荷量少,不利于凝并過程的繼續(xù)進行。張向榮等[18-19]在理論分析和數(shù)值模擬的基礎上,通過求解荷電顆粒凝并數(shù)量平衡方程,比較了顆粒數(shù)量濃度在有外電場和無電場條件下的變化規(guī)律,定量分析了外電場對荷電顆粒凝并的影響。

上述已開展的顆粒荷電凝并研究工作,大部分是針對燃煤煙氣顆粒的凝并過程,柴油機顆粒相比于燃煤煙氣顆粒,顆粒粒徑更小、更不規(guī)則、化學組分更加復雜[20],因此其荷電性能、凝并過程也將發(fā)生顯著變化。朱澤洪[21]研究了交流荷電電壓對柴油機顆粒形貌的影響,同時研究了交流荷電電壓對DPF過濾效率的影響,結果表明交流電壓為6 kV時,顆粒質(zhì)量中位徑增加,DPF過濾效率增加。目前針對柴油機排氣顆粒雙極荷電凝并的研究鮮有報道。本文以高壓共軌柴油機排氣顆粒為研究對象,應用發(fā)動機排氣粒徑譜儀(engine exhaust particle sizerspectrometer,EEPS)和微粒采樣分析儀(AVL SPC472),研究了荷電電壓對顆粒數(shù)量濃度、質(zhì)量中位徑、總數(shù)量濃度和DPF捕集效率的影響規(guī)律。

1 試驗裝置與方法

1.1 試驗系統(tǒng)與設備

雙極荷電凝并試驗系統(tǒng)如圖 1所示,主要包括臺架系統(tǒng)、荷電與凝并裝置、測量系統(tǒng)等。臺架系統(tǒng)主要包括:電渦流測功機(CAC250,湘儀動力測試儀器有限公司),用來控制柴油機轉速和扭矩;YZ4DB1-40柴油機(濰柴動力揚州柴油機有限責任公司),其主要結構參數(shù)及性能如表1所示,試驗時不改變原機的噴油時刻、噴油壓力等控制參數(shù)。燃料為市購國Ⅳ0#柴油。

荷電與凝并裝置主要包括:TE4020高壓直流電源(大連泰思曼科技有限公司),用于對柴油機排氣顆粒荷以正、負電荷,該高壓電源可以在0~±50 kV連續(xù)可調(diào),最大輸出電流為1 mA;陶瓷電熱圈控制荷電處的排氣溫度,功率5 kW,溫度控制精度為±10 ℃。

測量系統(tǒng)主要包括:EEPS-3090發(fā)動機排氣粒徑譜儀(美國 TSI 公司)用于測試顆粒的數(shù)量濃度,該設備測量的粒徑范圍為5.6~560 nm,粒徑分辨率為16通道每10倍粒徑(共32通道),內(nèi)部安裝有兩級稀釋系統(tǒng),一級稀釋系統(tǒng)為旋轉盤式熱稀釋器,二級稀釋系數(shù)為熱空氣調(diào)節(jié)器系統(tǒng),采樣頻率為10 Hz,可直接在線測量發(fā)動機排氣顆粒的粒徑和數(shù)量,能夠滿足柴油機瞬態(tài)工況下對顆粒數(shù)量的測量要求;SPC472微粒采樣分析儀(奧地利AVL公司),用來采集柴油機排氣顆粒;MX-5型微克天平(瑞士梅特勒-托利多公司),精度 1μg,用于測量采集顆粒質(zhì)量。

表1 YZ4DB1-40型柴油機主要性能及結構參數(shù)Table 1 Properties and structure parameters of YZ4DB1-40 diesel engine

圖1 雙極荷電凝并試驗裝置系統(tǒng)圖Fig.1 Schematic diagram of bipolar charged coagulation experimental system

1.2 試驗設計

1.2.1 排氣顆粒數(shù)量濃度試驗

試驗選取柴油機最大扭矩轉速1 600 r/min和額定轉速2 600 r/min下25%、50%、75%和100%負荷作為試驗工況點。每個工況點下分別調(diào)節(jié)電壓為 0、±5、±10、±15和±20 kV(如±5 kV時,正高壓電源電壓為5 kV,負高壓電源為-5 kV)測量排氣顆粒數(shù)量濃度。為保證試驗結果的可靠性,柴油機冷卻水溫度、機油溫度分別達到80 ℃和90 ℃后進行測量;柴油機工況點發(fā)生改變時,柴油機穩(wěn)定運轉30 min后再進行測量;電壓改變時,高壓電源電壓穩(wěn)定5 min后再進行測量;為降低排氣溫度對顆粒荷電的影響,在荷電裝置安裝陶瓷電熱圈,設定溫度控制為300 ℃。試驗時EEPS-3090設定一級稀釋系統(tǒng)的稀釋比為 100∶1,二級稀釋系統(tǒng)的稀釋比為 2∶1,控制總稀釋比為200∶1;對排氣顆粒連續(xù)采集120 s,最終結果取120 s平均值。高壓電源工作時,其耗功率范圍為0~8 W,車載12 V或24 V直流電源能夠通過逆變電源輸出±20 kV直流電,對荷電裝置供電,為裝車實用提供了可能。

1.2.2 DPF捕集效率試驗

選取1 600 r/min下的50%負荷作為DPF捕集效率試驗的工況點,利用AVL SPC472分別采集DPF前后端的顆粒,采樣時間設定為30 min;用MX-5型微克天平測量采樣前后的濾紙質(zhì)量,采樣后濾紙質(zhì)量減去采樣前濾紙質(zhì)量即為此次采集的顆粒質(zhì)量。為保證測量精度,采樣濾紙在采樣前后分別放入干燥皿中干燥 2 h然后再進行稱質(zhì)量。DPF過濾體為壁流式陶瓷過濾體,其孔密度為100 CSI。

2 試驗結果與分析

2.1 荷電電壓對顆粒數(shù)量濃度的影響

柴油機顆粒按照粒徑大小,可以劃分為核模態(tài)顆粒和積聚態(tài)顆粒,其粒徑范圍分別為 5~50 nm 和 50~500 nm[1,22-23]。

圖2為柴油機在1 600和2 600 r/min時,25%、50%、75%和 100%負荷下,荷電電壓對柴油機排氣顆粒數(shù)量濃度的影響。從圖2中可以看出,在2種轉速下,不同負荷和不同電壓的顆粒數(shù)量濃度均為雙峰分布,峰值分別在8.06~12.4 nm和45.3~80.6 nm之間;0 kV時,2 600 r/min時的排氣顆粒數(shù)量濃度在4種負荷下均高于1 600 r/min時的濃度。0 kV時,25%、50%和75%負荷下45.3~80.6 nm峰值處的數(shù)量濃度明顯高于8.06~12.4 nm峰值處的數(shù)量濃度,而且75%負荷時45.3~80.6 nm峰值處的數(shù)量濃度最高;100%負荷時,2個峰值處的顆粒數(shù)量濃度基本相同,但8.06~12.4 nm峰值處的數(shù)量濃度明顯高于其他負荷。在4種負荷下,相比荷電電壓為0 kV,荷電電壓5、10、15、20 kV時,核模態(tài)顆粒和低于93.1 nm的積聚態(tài)顆粒的數(shù)量濃度降低,高于93.1 nm的積聚態(tài)顆粒數(shù)量濃度略有升高。隨著荷電電壓的升高,25%、50%和75%負荷時,45.3~80.6 nm峰值處顆粒數(shù)量濃度降幅明顯;在100%負荷時,8.06~12.4 nm之間的顆粒數(shù)目降幅明顯高于45.3~60.4 nm之間的顆粒。對于單分散顆粒,顆粒間的凝并系數(shù)與顆粒數(shù)量濃度的平方成正比[24];對于多分散顆粒由于小粒徑顆粒具有更高的擴散系數(shù)會進一步提高顆粒的凝并進程[25-26],顆粒帶有不同極性電荷后,由于異極性荷電顆粒間存在庫倫力,能夠增加顆粒間碰撞概率,提高凝并系數(shù)[27-28]。隨著荷電電壓的提高,荷電裝置內(nèi)的電場強度增大,致使顆粒荷電量增多,從而提高了異極性荷電顆粒間的庫侖力,進一步增大了碰撞概率,顆粒間的相互多次碰撞、凝并,導致小粒徑顆粒數(shù)量降低,同時部分顆粒粒徑增大,導致了小粒徑顆粒數(shù)量濃度隨荷電電壓升高而降低,大粒徑顆粒數(shù)量濃度增多的現(xiàn)象。在100%負荷時,由于8.06~12.4 nm峰值處的顆粒數(shù)量濃度較高,且?guī)в须姾傻男×筋w粒具有更高的擴散系數(shù),因此該峰值處顆粒數(shù)量濃度降幅明顯。

圖2 柴油機不同轉速不同負荷下排放顆粒數(shù)量濃度Fig.2 Diesel engine particles number concentration at different rotational speeds and loads

2.2 荷電電壓對顆??倲?shù)量濃度的影響

圖3為1 600和2 600 r/min時,在25%、50%、75%和100%負荷下,不同荷電電壓對柴油機排氣顆??倲?shù)量濃度及其變化率的影響。從圖3中可以看出,2種轉速時,4種負荷下的排氣顆??倲?shù)量濃度均隨著荷電電壓的升高降低;排氣顆粒總數(shù)量濃度降幅隨著荷電電壓升高而增大。顆??倲?shù)量濃度變化率由式(1)計算

式中R為顆??倲?shù)量濃度變化率,%;nt0為0 kV時的顆粒總數(shù)量濃度,顆/cm3;nti為荷電電壓不為0 kV時的顆??倲?shù)量濃度,顆/cm3。

100%負荷時,與0 kV相比,5、10、15和20 kV下的顆??倲?shù)量濃度在1 600 r/min時,分別降低了9.71%、16.78%、21.92%和25.18%;在2 600 r/min時,分別降低了11.21%、15.19%、21.91%和25.33%。在荷電電壓相同時,與其他3種負荷相比,100%負荷下顆粒總數(shù)量濃度降幅最大,其原因在于100%負荷下的小粒徑顆粒數(shù)量濃度最高,由于其具有更高的擴散系數(shù),增大了與其它顆粒的碰撞概率,提高了凝并系數(shù),因此100%負荷下的顆??倲?shù)量降低明顯。

圖3 柴油機不同轉速不同負荷下的排放顆粒總數(shù)量濃度Fig. 3 Total particles number concentration at different rotational speeds and loads of diesel engine

2.3 荷電電壓對質(zhì)量密度分布和質(zhì)量中位徑的影響

選取質(zhì)量密度分布和質(zhì)量累積分布作為顆粒分散度的評價指標[29-30]。顆粒質(zhì)量密度分布由式(2)計算

式中fm為顆粒密度分布;ni為第i個區(qū)間離子數(shù)目,顆/cm3;dpi為第i個區(qū)間里的顆粒粒徑,nm;Δdpi為第i個區(qū)間的粒徑范圍,nm。

質(zhì)量累積分布定義為小于某一粒徑的所有粒子的質(zhì)量占總質(zhì)量的分數(shù),由式(3)計算

式中Fm為顆粒質(zhì)量累積分布;dp為顆粒粒徑,nm。

顆粒質(zhì)量累積分布 50%時所對應的顆粒粒徑稱為質(zhì)量中位徑,記作dpm50,可以近似代替顆粒幾何平均粒徑。圖4為1 600 r/min時,不同荷電電壓下的柴油機排氣顆粒質(zhì)量密度分布圖。由圖 4可以看出,隨著荷電電壓升高,核模態(tài)顆粒和低于93.1 nm的積聚態(tài)顆粒的質(zhì)量密度降低,高于93.1 nm的積聚態(tài)顆粒質(zhì)量密度升高,顆粒質(zhì)量密度分布向大粒徑方向偏移,同時峰值增大,且峰值對應的顆粒粒徑增加。20 kV時,顆粒質(zhì)量密度分布峰值最大,與0 kV相比,25%、50%、75%和100%負荷下的顆粒質(zhì)量密度分布峰值分別提高了8.06%、9.92%、9.51%和7.28%。

圖4 柴油機1 600 r·min-1時不同負荷下的排放顆粒質(zhì)量密度分布Fig. 4 Distribution of particles mass density under different diesel engine load at 1 600 r·min-1

圖5為1 600 r/min時,4種負荷下的顆粒質(zhì)量累積分布隨荷電電壓的變化規(guī)律,由圖 5中可以看出,隨著荷電電壓的增高,顆粒質(zhì)量累積分布曲線向大粒徑方向移動,荷電電壓越高,偏移量越大。其原因為荷電電壓增加后,顆粒荷電量增加,異極性顆粒間的庫侖力增大,凝并過程增強,單位時間內(nèi)顆粒碰撞的次數(shù)增加,導致顆粒粒徑變大。

圖6給出了1 600和2 600 r/min轉速時,4種負荷下排氣顆粒質(zhì)量中位徑及其變化率隨荷電電壓的變化。從圖6中可以看出,在相同負荷下,與1 600 r/min相比,2 600 r/min轉速下的排氣顆粒質(zhì)量中位徑略高;2種轉速時,與其他負荷相比,75%負荷下的排氣顆粒質(zhì)量中位徑最大。在2種轉速下,與0 kV時相比,4種負荷的排氣顆粒質(zhì)量中位徑均隨著荷電電壓的增加而增大,質(zhì)量中位徑范圍由96~101 nm增大至102~110 nm;在同一負荷下,荷電電壓越高,質(zhì)量中位徑增幅越大。其原因主要是荷電電壓越高,顆粒荷電量越大,顆粒間的庫倫凝并系數(shù)越高,在相同凝并時間內(nèi),顆粒碰撞頻率越高,由小粒徑顆粒凝并形成的大粒徑顆粒數(shù)目增加,大粒徑顆粒所占比重上升。

圖5 柴油機1 600 r·min-1時的排放顆粒質(zhì)量累積分布Fig. 5 Distribution of particles mass accumulation at 1 600 r·min-1 of diesel engine

圖6 柴油機不同轉速不同負荷下排放顆粒質(zhì)量中位徑及其變化率Fig. 6 Particles mass median diameter and change rate at different rotational speeds and loads of diesel engine

2.4 荷電電壓對DPF捕集效率的影響

捕集效率η是評價DPF性能的重要指標

式中η為DPF捕集效率,%;m1為在DPF前端采集的顆粒質(zhì)量,mg;m2為在DPF后端采集的顆粒質(zhì)量,mg。

圖7為1 600 r/min,50%負荷時荷電凝并(荷電時的電壓為10 kV)前后DPF捕集效率的變化規(guī)律。從圖7中可以看出柴油機排氣顆粒經(jīng)荷電凝并后,從DPF后端采集的顆粒質(zhì)量明顯降低,連續(xù)3次試驗結果顯示,DPF后的顆粒質(zhì)量分別從0 kV時的0.243、0.237和0.224 mg下降到10 kV時的0.115、0.121和0.117 mg,分別下降了52.7%、48.9%和47.8%;平均顆粒質(zhì)量從0.235 mg下降到0.118 mg,下降了49.8%。與0 kV時相比,10 kV時DPF的平均捕集效率由82.1%增加到91.1%,提高了9個百分點。由此可見,在不改變DPF過濾體結構參數(shù)的情況下,雙極荷電凝并能夠提高DPF捕集效率,同時降低顆粒數(shù)量與質(zhì)量排放。

圖7 1 600 r·min-1轉速下柴油機在荷電電壓 0和10 kV下DPF的捕集效率(50%負荷)Fig. 7 Trap efficiency of DPF at charged voltage 0 and10 kV at 1600 r·min-1 of diesel engine(50% load)

3 結 論

1)雙極荷電凝并能夠降低柴油機排氣顆粒的數(shù)量濃度,隨著荷電電壓的升高,核模態(tài)顆粒數(shù)量濃度降低,大于93.1 nm的積聚態(tài)顆粒數(shù)量濃度略有升高。25%負荷、50%負荷和75%負荷時,45.3~80.6 nm峰值處顆粒數(shù)量濃度隨荷電電壓的升高降幅明顯;100%負荷時,8.06~12.4 nm峰值處顆粒數(shù)量濃度降低幅度最大。

2)顆粒總數(shù)量濃度隨荷電電壓的升高而降低,荷電電壓越高,降幅越大;顆粒質(zhì)量濃度峰值、顆粒質(zhì)量中位徑均隨荷電電壓的升高而增加,荷電電壓越高,增幅越明顯。

3)雙極荷電凝并能夠提高DPF的捕集效率,降低柴油機排氣顆粒的數(shù)量和質(zhì)量排放,荷電電壓為10 kV時DPF的捕集效率較0 kV提高了9個百分點。

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Experimental research on decreasing particles emission number of diesel engine by bipolar charged coagulation

Meng Jian1,2, Liu Junheng1※, Sun Ping1, Wan Yaofeng1, Fan Yi1
(1.School of Automobile and Traffic Engineering, Jiangsu University, Zhenjiang212013,China;2.School of Transportation and Vehicle Engineering, Shandong University of Technology, Zibo255049,China)

It is difficult to control the particle number emission of diesel engine due to the high number concentration of nanometer particles. To solve this problem, a self-made bipolar charged coagulation test-bed was designed in this study to study the relationship between the particle number concentration of diesel engine and charged voltage. The particle number concentration, particle mass density distribution, particle total number concentration, particle mass median diameter of a common rail diesel engine (the operation conditions of diesel engine were 25% load, 50% load, 75% load and 100% load at 1,600 r/min and 2,600 r/min) under different charged voltages(0, 5, 10, 15 and 20 kV) were measured using an engine exhaust particle sizer spectrometer (EEPS-3090). The trap efficiency of diesel particulate filter (DPF) under 0 kV and 10 kV charged voltages at 50% load was measured using particle collection system (AVL SPC 472) and a microgram electronic balance (MX-5). Experimental results showed that bipolar charged coagulation could reduce the total particle number concentration of diesel engine. With the increase of charged voltage, at 50% load, the particle number concentration of nuclear mode particles (5~50 nm) and accumulation mode particles (<93.1 nm) were reduced, and the number concentration of accumulation mode particles (>93.1 nm) increased slightly, and at the same time the peak of particle number concentration dropped significantly. At 100% load, with the increase of charged voltage, the particle number concentration of diesel engine was in a normal bimodal distribution obviously under different charged voltage, the number concentration of decreased nuclear mode particles (5~50nm) and accumulation mode particles (<93.1 nm) reduced sharply, and the number concentration of accumulation mode particles (>93.1 nm) decreased slightly. At 100% load, the particle number concentration decreased mostly in the number concentration peak of small particles. With the increase of charged voltage, the particle total number concentration decreased. At 50% load, compared with 0 kV, the particle total number concentration decreased by 9.28%,16.23%, 18.17% and 20.56% for 5, 10, 15 and 20 kV, respectively. While at 100% load, compared with 0 kV, the particle total number concentration decreased by 9.71%、16.78%、21.92% and 25.18% for 5, 10, 15 and 20 kV, respectively. At the same charged voltage, the particle total number concentration at 100% load decreased more obviously than 25% load, 50% load and 75% load. With the increase of charged voltage, the peak of particle mass density distribution moved to larger particles.Compared with 0 kV, the peak of particle mass density distribution at 20 kV increased by 8.06%、9.92%、9.51% and 7.28% for 25% load, 50% load, 75% load and 100% load, respectively. The curves of particle mass cumulative distribution moved to larger particles with the increase of charged voltage at 25% load, 50% load, 75% load and 100% load. With the increase of charged voltage from to 0 kV to 20 kV, the range of particle mass median diameter increased from 96~101 nm to 102~110 nm.Compared with 0 kV, the trap efficiency of DPF (diesel particulate filter) at 10 kV increased from 82.1% to 91.1%. In summary, bipolar charged coagulation could increase the trap efficiency of DPF, and reduce the particle number emission and particle mass emission of diesel engine. The results can provide a technical reference for the application of bipolar charged voltage in automobile.

diesel engines; emission control; particles; bipolar charge; particle number concentration; trap efficiency

10.11975/j.issn.1002-6819.2017.14.011

TK421+.5

A

1002-6819(2017)-14-0078-07

孟 建,劉軍恒,孫 平,萬垚峰,范 義. 雙極荷電凝并降低柴油機顆粒排放數(shù)量的試驗研究[J]. 農(nóng)業(yè)工程學報,2017,33(14):78-84.

10.11975/j.issn.1002-6819.2017.14.011 http://www.tcsae.org

Meng Jian, Liu Junheng, Sun Ping, Wan Yaofeng, Fan Yi. Experimental research on decreasing particles emission number of diesel engine by bipolar charged coagulation[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2017, 33(14): 78-84. (in Chinese with English abstract) doi:10.11975/j.issn.1002-6819.2017.14.011 http://www.tcsae.org

2017-01-11

2017-05-29

江蘇省高校自然科學研究重大項目(10KJA470001);江蘇省自然科學基金(BK20160538);江蘇省高校自然科學研究面上項目資助(16KJB470003);內(nèi)燃機燃燒學國家重點實驗室開放基金資助項目(K2016-05);國家自然科學基金資助項目(51249001)

孟 建,男,山東滕州,博士,講師,主要從事內(nèi)燃機排放與控制方面研究。鎮(zhèn)江 江蘇大學汽車與車輛工程學院,212013。

Email:tzwzmj@163.com

※通信作者:劉軍恒,男,河南安陽,講師,博士,主要從事內(nèi)燃機燃燒與排放控制技術研究。鎮(zhèn)江 江蘇大學汽車與交通工程學院,212013。

Email:liujunheng@ujs.edu.cn

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