均质化学计量比燃烧下GDI发动机碳烟生成可视化解析
|
摘要
汽油机燃烧过程中产生的黄色火焰与生成的碳烟呈正相关,根据这一特征,利用高速摄影获取汽油直喷(GDI)光学发动机缸内的火焰图片,通过统计计算其中黄色火焰的信号强度,分析了缸内碳烟的生成规律以及燃料中甲苯、乙醇含量对缸内碳烟生成的影响.结果表明:在化学计量比燃烧条件下,碳烟在点火初期火花塞电极附近产生,这部分碳烟的滞留时间相对较长,整个燃烧过程中,碳烟的产生主要位于火花塞附近.甲苯比例的增加对碳烟生成有明显的促进作用;而添加乙醇能够抑制缸内碳烟总体生成量,但在点火之后的1°CA内,黄色火焰信号强度没有降低,表明该时期碳烟的生成无法得到有效抑制.
The yellow flame generating during the combustion is positively related to the soot. According to this characteristic,high-speed photography was used to obtain the pictures of flame in the cylinder of an optical gasoline direct injection(GDI) engine. The generation process of soot and the influence of toluene and ethanol on soot generation were analyzed by statistically calculating the signal intensity of the yellow flame. The results show that,under homogeneous stoichiometric combustion,the soot initially generates in the vicinity of the spark plug electrode when the ignition occurs. This type of soot has relatively long residence time,and the soot mainly generate near the spark plug overall. Toluene can significantly promote the generation of soot. The addition of ethanol can suppress the generation of soot during combustion,but it cannot decrease the signal intensity of the yellow flame within about 1° CA after ignition,indicating that the generation of soot cannot be effectively suppressed at this stage.
The yellow flame generating during the combustion is positively related to the soot. According to this characteristic,high-speed photography was used to obtain the pictures of flame in the cylinder of an optical gasoline direct injection(GDI) engine. The generation process of soot and the influence of toluene and ethanol on soot generation were analyzed by statistically calculating the signal intensity of the yellow flame. The results show that,under homogeneous stoichiometric combustion,the soot initially generates in the vicinity of the spark plug electrode when the ignition occurs. This type of soot has relatively long residence time,and the soot mainly generate near the spark plug overall. Toluene can significantly promote the generation of soot. The addition of ethanol can suppress the generation of soot during combustion,but it cannot decrease the signal intensity of the yellow flame within about 1° CA after ignition,indicating that the generation of soot cannot be effectively suppressed at this stage.
引文
[1]Myung C L,Park S.Exhaust nanoparticle emissions from internal combustion engines:A review[J].International Journal of Automotive Technology,2012,13(1):9-22
[2]帅石金,董哲林,郑荣,等.车用汽油机颗粒物生成机理及排放特性研究进展[J].内燃机学报,2016,34(2):105-116.
[3]Braisher M,Stone R,Price P.Particle number emissions from a range of European vehicles[C]//SAE Paper.Detroit,Michigan,USA,2010,2010-01-0786.
[4]Maikawa C L,Zimmerman N,Rais K,et al.Murine precision-cut lung slices exhibit acute responses following exposure to gasoline direct injection engine emissions[J].The Science of the Total Environment,2016,568:1102-1109.
[5]Larsson B-M,Sehlstedt M,Grunewald J,et al.Road tunnel air pollution induces bronchoalveolar inflammation in healthy subjects[J].European Respiratory Journal,2007,29(4):699-705.
[6]Block B,Oppermann W,Ag A,et al.Luminosity and laser-induced incandescence investigations on a DI gasoline engine[C]//SAE Paper.Baltimore,Maryland,USA,2000,2000-01-2903.
[7]Velji A,Yeom K,Wagner U,et al.Investigations of the formation and oxidation of soot inside a direct injection spark ignition engine using advanced lasertechniques[C]//SAE Paper.Detroit,Michigan,USA,2010,2010-01-0352.
[8]Francqueville L,Bruneaux G,Thirouard B.Soot volume fraction measurements in a gasoline direct injection engine by combined laser induced incandescence and laser extinction method[J].SAE International Journal of Engines,2010,3(1):163-182.
[9]Storch M,Zigan L,Wensing M,et al.Systematic investigation of the influence of ethanol blending on sooting combustion in DISI engines using high-speed imaging and LII[C]//SAE Paper.Birmingham,Alabama,United Kingdom,2014,2014-01-2617.
[10]Storch M,Hinrichsen F,Wensing M,et al.The effect of ethanol blending on mixture formation,combustion and soot emission studied in an optical DISI engine[J].Applied Energy,2015,156:783-792.
[11]Storch M,Koegl M,Altenhoff M,et al.Investigation of soot formation of spark-ignited ethanol-blended gasoline sprays with single-and multi-component base fuels[J].Applied Energy,2016,181:278-287.
[12]郑亮.用激光诱导炽光法研究燃烧过程中的碳烟生成特性[D].北京:清华大学机械工程学院,2014.
[13]Jakob M,Hülser T,Janssen A,et al.Simultaneous high-speed visualization of soot luminosity and OHchemiluminescence of alternative-fuel combustion in a HSDI diesel engine under realistic operating conditions[J].Combustion and Flame,2012,159(7):2516-2529.
[14]Yang J,Dong X,Wu Q,et al.Influence of flash boiling spray on the combustion characteristics of a sparkignition direct-injection optical engine under cold start[J].Combustion and Flame,2018,188:66-76.
[15]Ma X,Li Y,Qi Y,et al.Optical study of throttleless and EGR-controlled stoichiometric dual-fuel compression ignition combustion[J].Fuel,2016,182:272-283.
[16]Johansen L C R,Hemdal S.In cylinder visualization of stratified combustion of E85 and main sources of soot formation[J].Fuel,2015,159:392-411.
[17]梁帅,张周,丁海春,等.用PLIF测量GDI发动机滚流平面的混合气浓度[J].内燃机学报,2018,36(6):481-490.
[18]Mueller C J,Martin G C.Effects of oxygenated compounds on combustion and soot evolution in a DI diesel engine:Broadband natural luminosity imaging[C]//SAE Paper.Reno,Nevada,USA,2002,2002-01-1631.
[19]Zhang M,Drake M C,Peterson K.Simultaneous highspeed imaging of fuel spray,combustion luminosity,and soot luminosity in a spray-guided direct injection engine with different multi-hole fuel injectors[C]//ASME2013 Internal Combustion Engine Division Fall Technical Conference.Dearborn,Michigan,USA,2013,V001T03A007.
[20]Smith A R.Color gamut transform pairs[J].ACM Siggraph Computer Graphics,1978,12(3):12-19.
[21]Berndorfer A,Breuer S,Piock W,et al.Diffusion combustion phenomena in GDI engines caused by injection process[C]//SAE Paper.Detroit,Michigan,USA,2013,2013-01-0261.
[22]Raj A,Prada I D C,Amer A A,et al.A reaction mechanism for gasoline surrogate fuels for large polycyclic aromatic hydrocarbons[J].Combustion and Flame,2012,159(2):500-515.
[23]Lemaire R,Therssen E,Desgroux P.Effect of ethanol addition in gasoline and gasoline-surrogate on soot formation in turbulent spray flames[J].Fuel,2010,89(12):3952-3959.
[24]Xu H,Yao C,Xu G,et al.Experimental and modelling studies of the effects of methanol and ethanol addition on the laminar premixed low-pressure nheptane/toluene flames[J].Combustion and Flame,2013,160(8):1333-1344.
[25]Kammermann T,Kreutner W,Trottmann M,et al.Spark-induced breakdown spectroscopy of methane/air and hydrogen-enriched methane/air mixtures at engine relevant conditions[J].Spectrochimica Acta Part B:Atomic Spectroscopy,2018,148:152-164.
[26]Kawahara N,Hashimoto S,Tomita E.Spark discharge ignition process in a spark-ignition engine using a time series of spectra measurements[J].Proceedings of the Combustion Institute,2017,36(3):3451-3458.
[27]Irimescu A,Merola S.Spark discharge and flame inception analysis through spectroscopy in a DISI engine fuelled with gasoline and butanol[C]//IOP Publishing.Pitesti,Arges,Romania,2017,012093.
[28]Merola S S,Di Iorio S,Irimescu A,et al.Spectroscopic characterization of energy transfer and thermal conditions of the flame kernel in a spark ignition engine fueled with methane and hydrogen[J].International Journal of Hydrogen Energy,2017,42(18):13276-13288.
[29]Hemdal S,Andersson M,Dahlander P,et al.Incylinder soot imaging and emissions of stratified combustion in a spark-ignited spray-guided direct-injection gasoline engine[J].International Journal of Engine Research,2011,12(6):549-563.
[30]Griffin E A,Christensen M,Gülder?L.Effect of ethanol addition on soot formation in laminar methane diffusion flames at pressures above atmospheric[J].Combustion and Flame,2018,193:306-312.
[2]帅石金,董哲林,郑荣,等.车用汽油机颗粒物生成机理及排放特性研究进展[J].内燃机学报,2016,34(2):105-116.
[3]Braisher M,Stone R,Price P.Particle number emissions from a range of European vehicles[C]//SAE Paper.Detroit,Michigan,USA,2010,2010-01-0786.
[4]Maikawa C L,Zimmerman N,Rais K,et al.Murine precision-cut lung slices exhibit acute responses following exposure to gasoline direct injection engine emissions[J].The Science of the Total Environment,2016,568:1102-1109.
[5]Larsson B-M,Sehlstedt M,Grunewald J,et al.Road tunnel air pollution induces bronchoalveolar inflammation in healthy subjects[J].European Respiratory Journal,2007,29(4):699-705.
[6]Block B,Oppermann W,Ag A,et al.Luminosity and laser-induced incandescence investigations on a DI gasoline engine[C]//SAE Paper.Baltimore,Maryland,USA,2000,2000-01-2903.
[7]Velji A,Yeom K,Wagner U,et al.Investigations of the formation and oxidation of soot inside a direct injection spark ignition engine using advanced lasertechniques[C]//SAE Paper.Detroit,Michigan,USA,2010,2010-01-0352.
[8]Francqueville L,Bruneaux G,Thirouard B.Soot volume fraction measurements in a gasoline direct injection engine by combined laser induced incandescence and laser extinction method[J].SAE International Journal of Engines,2010,3(1):163-182.
[9]Storch M,Zigan L,Wensing M,et al.Systematic investigation of the influence of ethanol blending on sooting combustion in DISI engines using high-speed imaging and LII[C]//SAE Paper.Birmingham,Alabama,United Kingdom,2014,2014-01-2617.
[10]Storch M,Hinrichsen F,Wensing M,et al.The effect of ethanol blending on mixture formation,combustion and soot emission studied in an optical DISI engine[J].Applied Energy,2015,156:783-792.
[11]Storch M,Koegl M,Altenhoff M,et al.Investigation of soot formation of spark-ignited ethanol-blended gasoline sprays with single-and multi-component base fuels[J].Applied Energy,2016,181:278-287.
[12]郑亮.用激光诱导炽光法研究燃烧过程中的碳烟生成特性[D].北京:清华大学机械工程学院,2014.
[13]Jakob M,Hülser T,Janssen A,et al.Simultaneous high-speed visualization of soot luminosity and OHchemiluminescence of alternative-fuel combustion in a HSDI diesel engine under realistic operating conditions[J].Combustion and Flame,2012,159(7):2516-2529.
[14]Yang J,Dong X,Wu Q,et al.Influence of flash boiling spray on the combustion characteristics of a sparkignition direct-injection optical engine under cold start[J].Combustion and Flame,2018,188:66-76.
[15]Ma X,Li Y,Qi Y,et al.Optical study of throttleless and EGR-controlled stoichiometric dual-fuel compression ignition combustion[J].Fuel,2016,182:272-283.
[16]Johansen L C R,Hemdal S.In cylinder visualization of stratified combustion of E85 and main sources of soot formation[J].Fuel,2015,159:392-411.
[17]梁帅,张周,丁海春,等.用PLIF测量GDI发动机滚流平面的混合气浓度[J].内燃机学报,2018,36(6):481-490.
[18]Mueller C J,Martin G C.Effects of oxygenated compounds on combustion and soot evolution in a DI diesel engine:Broadband natural luminosity imaging[C]//SAE Paper.Reno,Nevada,USA,2002,2002-01-1631.
[19]Zhang M,Drake M C,Peterson K.Simultaneous highspeed imaging of fuel spray,combustion luminosity,and soot luminosity in a spray-guided direct injection engine with different multi-hole fuel injectors[C]//ASME2013 Internal Combustion Engine Division Fall Technical Conference.Dearborn,Michigan,USA,2013,V001T03A007.
[20]Smith A R.Color gamut transform pairs[J].ACM Siggraph Computer Graphics,1978,12(3):12-19.
[21]Berndorfer A,Breuer S,Piock W,et al.Diffusion combustion phenomena in GDI engines caused by injection process[C]//SAE Paper.Detroit,Michigan,USA,2013,2013-01-0261.
[22]Raj A,Prada I D C,Amer A A,et al.A reaction mechanism for gasoline surrogate fuels for large polycyclic aromatic hydrocarbons[J].Combustion and Flame,2012,159(2):500-515.
[23]Lemaire R,Therssen E,Desgroux P.Effect of ethanol addition in gasoline and gasoline-surrogate on soot formation in turbulent spray flames[J].Fuel,2010,89(12):3952-3959.
[24]Xu H,Yao C,Xu G,et al.Experimental and modelling studies of the effects of methanol and ethanol addition on the laminar premixed low-pressure nheptane/toluene flames[J].Combustion and Flame,2013,160(8):1333-1344.
[25]Kammermann T,Kreutner W,Trottmann M,et al.Spark-induced breakdown spectroscopy of methane/air and hydrogen-enriched methane/air mixtures at engine relevant conditions[J].Spectrochimica Acta Part B:Atomic Spectroscopy,2018,148:152-164.
[26]Kawahara N,Hashimoto S,Tomita E.Spark discharge ignition process in a spark-ignition engine using a time series of spectra measurements[J].Proceedings of the Combustion Institute,2017,36(3):3451-3458.
[27]Irimescu A,Merola S.Spark discharge and flame inception analysis through spectroscopy in a DISI engine fuelled with gasoline and butanol[C]//IOP Publishing.Pitesti,Arges,Romania,2017,012093.
[28]Merola S S,Di Iorio S,Irimescu A,et al.Spectroscopic characterization of energy transfer and thermal conditions of the flame kernel in a spark ignition engine fueled with methane and hydrogen[J].International Journal of Hydrogen Energy,2017,42(18):13276-13288.
[29]Hemdal S,Andersson M,Dahlander P,et al.Incylinder soot imaging and emissions of stratified combustion in a spark-ignited spray-guided direct-injection gasoline engine[J].International Journal of Engine Research,2011,12(6):549-563.
[30]Griffin E A,Christensen M,Gülder?L.Effect of ethanol addition on soot formation in laminar methane diffusion flames at pressures above atmospheric[J].Combustion and Flame,2018,193:306-312.