低压直喷发动机稀释燃烧优化及爆震控制研究
摘要
当今世界,能源的发展和环境保护是全人类共同关心的焦点,也是我国社会经济发展的重要问题,内燃机的主要发展方向是改进燃烧过程,提高机械效率,减少热损失,降低燃料消耗率,减轻对环境的污染。喷雾引导的缸内直喷技术是提高发动机热效率,降低排放,降低燃油消耗的有效手段。低压空气辅助直喷发动机相比于高压直喷发动机具有更好的雾化效果稳定性,且降低了成本,更具有市场应用价值,研究表明,低压缸内直喷发动机采用稀释混合气燃烧,可以使用较高压缩比,使热效率提高,在部分负荷时,可以通过加大节气门开度减小节流损失,能够改善燃油经济性,稀释燃烧技术可有效的降低最高燃烧温度,从而抑制爆震的发生。本文围绕这几个关键的问题对低压直喷发动机进行了稀释燃烧优化,并对爆震控制进行了研究。具体研究内容如下:
1.研制了发动机综合数据采集系统,整合了台架试验所用的设备,通过设备的数据通讯接口将各设备数据同步上传到数据采集系统,搭建了一个完整的发动机台架,建立了良好的试验平台。
2.研制基于CCP协议的发动机标定系统,采用CAN网络与被标定的控制单元进行通信,实现对控制单元参数的调节以及对数据的上传和下载。
3.研制了发动机燃烧分析系统及爆震采集模块。燃烧分析系统可以实时监测气缸压力曲线及基于示功图进行燃烧分析,可得到燃烧放热率、压力升高率、累积放热率、IMEP、循环变动等燃烧参数;提出了一种时域信号积分和频域信号积分相结合的快速爆震检测算法,可以对发动机进行实时的爆震监测。
4.利用发动机标定系统和燃烧分析系统,监测发动机的燃烧过程,通过优化点火提前角、空燃比、EGR率等参数,研究稀释燃烧参数的变化的规律。研究结果表明EGR率在5%-20%之间燃烧循环变动较小,可有效降低燃油消耗率8%-21%
5.利用发动机标定系统和燃烧分析系统爆震采集模块,通过点火提前角、EGR率、空燃比等参数的调整,研究爆震的控制方法。研究结果表明当量空燃比下EGR率每增加5%,爆震极限点火提前角平均可提前2°CA.
Nowadays, the power development and environment protection are the common problems all over the world, they also affect Chinese economy development, and the development of internal combustion engine affects these two aspects directly, so it is significant to improve the engine performance. At present, the main developing way is improving combustion process, increasing mechanical efficiency and decreasing heat loss for lower fuel consumption, and many technologies were used to reduce the emission such as HC, CO and NOx. Gasoline direct injection, diluted combustion can availably improve engine thermal efficiency and reduce harmful emission. Studies have shown that GDI engine could have a large compression ratio due to the lean mixture in the cylinder, the way of quality adjustment at part-load operating condition can reduce the throttling loss, so good economy performance will resulted from GDI technology. Exhaust gas recirculation(EGR)could reduce the in-cylinder temperature, which could result in low NOx emission, additionally, appropriate EGR ratio could also decrease the opportunity of Knock happening. This paper shown the diluted combustion optimiztion and the study about knock control for low-pressure GDI engine, and follows the main contents:
1. Prepared the data acquisition (DAQ) system and the whole equipment will be used, and then upload the data of equipments to DAQ system through data communication interface, which conveniences the task data acquisition and post-processing.
2. Finished the engine calibration system based on CCP protocol, communicating with control unit through Controller Area Network (CAN), which realized the data adjustment, upload and download.
3. Finished engine combustion analysis system and knock signal acquisition module. The combustion analysis system has a real-time monitoring of in-cylinder pressure and analyzes the signal, then other important information will be obtained, such as heat release rate, pressure rise rate, cumulative heat release rate, IMEP, COV, and so on. What’s more, real-time monitoring of knock could realized according to the analysis of cylinder pressure curve.
4. Calibration system and combustion analysis system were used to monitor the engine combustion process, studied the diluted combustion law via adjusting the advanced ignition angle, A/F ratio and EGR ratio. The results demonstrate that engine has a lower cycle-to-cycle variation ratio with the EGR ratio range from 5% to 20%, and fuel consumption will decrease by 8%-21%.
5. A knock signal acquisition module was used to research the method of knock controlling via adjusting the parameter such as advanced ignition angle, EGR ratio and A/F ratio. At operating conditions of stoicheiometry A/F ratio, results show that the ignition angle limited by detonation can be advanced by 2 crank angles with every 5% increase of EGR ratio.
1.研制了发动机综合数据采集系统,整合了台架试验所用的设备,通过设备的数据通讯接口将各设备数据同步上传到数据采集系统,搭建了一个完整的发动机台架,建立了良好的试验平台。
2.研制基于CCP协议的发动机标定系统,采用CAN网络与被标定的控制单元进行通信,实现对控制单元参数的调节以及对数据的上传和下载。
3.研制了发动机燃烧分析系统及爆震采集模块。燃烧分析系统可以实时监测气缸压力曲线及基于示功图进行燃烧分析,可得到燃烧放热率、压力升高率、累积放热率、IMEP、循环变动等燃烧参数;提出了一种时域信号积分和频域信号积分相结合的快速爆震检测算法,可以对发动机进行实时的爆震监测。
4.利用发动机标定系统和燃烧分析系统,监测发动机的燃烧过程,通过优化点火提前角、空燃比、EGR率等参数,研究稀释燃烧参数的变化的规律。研究结果表明EGR率在5%-20%之间燃烧循环变动较小,可有效降低燃油消耗率8%-21%
5.利用发动机标定系统和燃烧分析系统爆震采集模块,通过点火提前角、EGR率、空燃比等参数的调整,研究爆震的控制方法。研究结果表明当量空燃比下EGR率每增加5%,爆震极限点火提前角平均可提前2°CA.
Nowadays, the power development and environment protection are the common problems all over the world, they also affect Chinese economy development, and the development of internal combustion engine affects these two aspects directly, so it is significant to improve the engine performance. At present, the main developing way is improving combustion process, increasing mechanical efficiency and decreasing heat loss for lower fuel consumption, and many technologies were used to reduce the emission such as HC, CO and NOx. Gasoline direct injection, diluted combustion can availably improve engine thermal efficiency and reduce harmful emission. Studies have shown that GDI engine could have a large compression ratio due to the lean mixture in the cylinder, the way of quality adjustment at part-load operating condition can reduce the throttling loss, so good economy performance will resulted from GDI technology. Exhaust gas recirculation(EGR)could reduce the in-cylinder temperature, which could result in low NOx emission, additionally, appropriate EGR ratio could also decrease the opportunity of Knock happening. This paper shown the diluted combustion optimiztion and the study about knock control for low-pressure GDI engine, and follows the main contents:
1. Prepared the data acquisition (DAQ) system and the whole equipment will be used, and then upload the data of equipments to DAQ system through data communication interface, which conveniences the task data acquisition and post-processing.
2. Finished the engine calibration system based on CCP protocol, communicating with control unit through Controller Area Network (CAN), which realized the data adjustment, upload and download.
3. Finished engine combustion analysis system and knock signal acquisition module. The combustion analysis system has a real-time monitoring of in-cylinder pressure and analyzes the signal, then other important information will be obtained, such as heat release rate, pressure rise rate, cumulative heat release rate, IMEP, COV, and so on. What’s more, real-time monitoring of knock could realized according to the analysis of cylinder pressure curve.
4. Calibration system and combustion analysis system were used to monitor the engine combustion process, studied the diluted combustion law via adjusting the advanced ignition angle, A/F ratio and EGR ratio. The results demonstrate that engine has a lower cycle-to-cycle variation ratio with the EGR ratio range from 5% to 20%, and fuel consumption will decrease by 8%-21%.
5. A knock signal acquisition module was used to research the method of knock controlling via adjusting the parameter such as advanced ignition angle, EGR ratio and A/F ratio. At operating conditions of stoicheiometry A/F ratio, results show that the ignition angle limited by detonation can be advanced by 2 crank angles with every 5% increase of EGR ratio.
引文
[1]夏淑敏,车用汽油机缸内直喷技术的研究现状与展望,农业机械学报,2003
[2]杨世春,缸内直喷汽油机技术发展趋势分析,车用发动机,2007
[3]李彧, GDI发动机研究概况,内燃机,2006
[4]赵育新,GDI的发展现状及发展趋势分析,科技信息,2009
[5]吴憩棠,美国《Wards Auto World》评出2007年度世界十佳发动机,汽车与配件,2007
[6]清水,奥迪2.0 TFSI第四次入选全球十佳发动机,中国汽车界2010
[7]嵇全喜,GDI发动机冷启动控制策略研究,[硕士学位论文],吉林;吉林大学,2011
[8]周华,汽油机缸内直喷稀薄燃烧技术(GDI),客车技术与研究,2007
[9]石浩天,GDI汽油机进气系统的数值模拟研究,[硕士学位论文],天津;天津大学,2008
[10]刘鑫,汽油机缸内直喷(GDI)稀薄燃烧技术,交通科技与经济,2011
[11]王建昕,高效清洁车用汽油机燃烧的研究进展,汽车安全与节能学报,2010
[12]Philipp Adomeit, Andreas Sehr, Operation Strategies for Controlled Auto Ignition Gasoline Engines, SAE2009-01-0300
[13]Fatih Sarikoc, Sebastian Hensel, Investigations on the Effects of the ignition Spark with Controlled Autoignition(CAI), SAE2009-01-1770
[14]Simon Brewster, Initial Development of a Turbo-charged Direct Injection E100 Combustion System, SAE2007-01-3625
[15] Callan Bleechmore, Dilution Strategies for Load and NOx Management in a Hydrogen Fuelled Direct Injection Engine, SAE2007-01-4097
[16] Simon Brewster, The Potential of Enhanced HCCI / CAI Control Through the Application of Spray Guided Direct Injection, SAE2008-01-0035
[17]朱昌吉,车用柴油机电控EGR系统设计及性能研究, [博士学位论文],吉林;吉林大学,2005
[18]Usman Asad, Efficacy of EGR and Boost in Single-Injection Enabled Low Temperature Combustion, SAE2009-01-1126
[19]吴平友,汽油发动机爆震分析与控制,内燃机学报,2003
[20]唐江,HCCI汽油机爆震控制的研究,[硕士学位论文],天津;天津大学,2008
[21]于文英,EGR对小型汽油机排放和性能影响的试验研究,小型内燃机与摩托车,2010
[22]王凤滨,EGR在内燃机上的应用,汽车工程师,2009
[23] Geoffrey Cathcart, Christian Zavier, Fundamental Characteristics of an Air-Assisted Direct Injection Combustion System as Applied to 4-Stroke Automotive Gasoline Engines, SAE2000-01-0256
[24] Geoffrey CATHCART, Don RAILTON, Improving Robustness of Spray Guided DI Combustion Systems: The Air-Assisted Approach, SAE20015360
[25]李立军,采用VVT技术的汽油机控制策略的研究,汽车工程学报,2011
[26]田硕,基于MMB和LABVIEW的电控柴油机标定系统,大连交通大学学报,2010
[27]吴志红,基于LabVIEW的汽车电子控制单元CCP标定系统设计,机械与电子,2008
[28]王伟达,汽车ASR系统ECU开发及其硬件在环测试,电子技术应用,2008
[29]ASAP Standard, Can Calibration Protocol Version 2.1, 1999
[30]林志华,基于CCP协议的电控发动机监控标定系统开发,汽车科技,2011
[31]王浩洁,基于LABVIEW的内燃机示功图模拟及燃烧分析系统开发,[硕士学位论文],四川;西南交通大学,2010
[32]催海龙,多缸发动机气缸压力采集与燃烧分析系统的研究,北京;北京工业大学,2003
[33]李秋风,内燃机燃烧分析测控系统开发,[硕士学位论文],天津;河北工业大学。
[34] NicosLadommatos. Engine Combustion Instrumentation and Dignostics , Society of Automotive Engineers,Inc, 2001
[35]AVL公司,AVL燃烧分析仪资料,2010
[36]FEV公司,FEV燃烧分析仪资料,2011
[37]奇石乐公司,奇石乐燃烧分析系统资料,2011
[38]田慧,栗保明,压电式压力传感器的测量与标定系统,电子元器件应用, 2008
[39]奇石乐扩展了其冲压力传感器系列,电机与控制应用, 2010
[40]奇石乐公司,奇石乐电荷放大器资料,2011
[41]长春光禹光学技术有限公司,光电编码器资料,2011
[42]北京阿尔泰科技有限公司,数据采集卡资料,2011
[43]美国国家仪器,labvIEW简介,2011
[44]邹喜红,压缩线法求动态上止点,小型内燃机与摩托车, 2003
[45]蒋德明,内燃机燃烧与排放学,西安,西安交通大学出版社,2001
[46]刘亮欣,黄佐华,蒋德明,天然气缸内直喷发动机燃烧循环变动特性研究,内燃机学报, 2005
[47]李兴虎,蒋德明,火花点火发动机压力循环变动的评价方法研究,内燃机学报, 2000
[48]侯圣智,HCCI汽油机混合燃烧及放热率计算模型,天津大学学报, 2009
[49]唐江,HCCI汽油机爆震控制研究,[硕士学位论文],天津;天津大学,2008
[50]黄希桥,严传俊,爆震频率对脉冲爆震发动机引射性能影响的试验,航空动力学报, 2008
[51]韩宇石,电控汽油机爆震信号分析与检测, [硕士学位论文],北京;北京工业大学, 2005
[52] Wu G, A real time statistical method for engine knock detection ,SAE2007-01-1507 [53]
[53] M.J. Kearney-Delphi,Knock signal conditioning using the discrete fourier transform and variable detection window length,SAE2007-01-1509
[54]徐帆,HCCI燃烧中爆震现象的研究及其控制策略,[硕士学位论文],北京;清华大学, 2011
[55]庄兵,彭飞舟,内燃机废气再循环(EGR)率评价方法分析,小型内燃机与摩托车, 2007
[56]郭鹏江,王天灵,利用文丘里管和VNT提高柴油机EGR率的研究,内燃机学报, 2009
[2]杨世春,缸内直喷汽油机技术发展趋势分析,车用发动机,2007
[3]李彧, GDI发动机研究概况,内燃机,2006
[4]赵育新,GDI的发展现状及发展趋势分析,科技信息,2009
[5]吴憩棠,美国《Wards Auto World》评出2007年度世界十佳发动机,汽车与配件,2007
[6]清水,奥迪2.0 TFSI第四次入选全球十佳发动机,中国汽车界2010
[7]嵇全喜,GDI发动机冷启动控制策略研究,[硕士学位论文],吉林;吉林大学,2011
[8]周华,汽油机缸内直喷稀薄燃烧技术(GDI),客车技术与研究,2007
[9]石浩天,GDI汽油机进气系统的数值模拟研究,[硕士学位论文],天津;天津大学,2008
[10]刘鑫,汽油机缸内直喷(GDI)稀薄燃烧技术,交通科技与经济,2011
[11]王建昕,高效清洁车用汽油机燃烧的研究进展,汽车安全与节能学报,2010
[12]Philipp Adomeit, Andreas Sehr, Operation Strategies for Controlled Auto Ignition Gasoline Engines, SAE2009-01-0300
[13]Fatih Sarikoc, Sebastian Hensel, Investigations on the Effects of the ignition Spark with Controlled Autoignition(CAI), SAE2009-01-1770
[14]Simon Brewster, Initial Development of a Turbo-charged Direct Injection E100 Combustion System, SAE2007-01-3625
[15] Callan Bleechmore, Dilution Strategies for Load and NOx Management in a Hydrogen Fuelled Direct Injection Engine, SAE2007-01-4097
[16] Simon Brewster, The Potential of Enhanced HCCI / CAI Control Through the Application of Spray Guided Direct Injection, SAE2008-01-0035
[17]朱昌吉,车用柴油机电控EGR系统设计及性能研究, [博士学位论文],吉林;吉林大学,2005
[18]Usman Asad, Efficacy of EGR and Boost in Single-Injection Enabled Low Temperature Combustion, SAE2009-01-1126
[19]吴平友,汽油发动机爆震分析与控制,内燃机学报,2003
[20]唐江,HCCI汽油机爆震控制的研究,[硕士学位论文],天津;天津大学,2008
[21]于文英,EGR对小型汽油机排放和性能影响的试验研究,小型内燃机与摩托车,2010
[22]王凤滨,EGR在内燃机上的应用,汽车工程师,2009
[23] Geoffrey Cathcart, Christian Zavier, Fundamental Characteristics of an Air-Assisted Direct Injection Combustion System as Applied to 4-Stroke Automotive Gasoline Engines, SAE2000-01-0256
[24] Geoffrey CATHCART, Don RAILTON, Improving Robustness of Spray Guided DI Combustion Systems: The Air-Assisted Approach, SAE20015360
[25]李立军,采用VVT技术的汽油机控制策略的研究,汽车工程学报,2011
[26]田硕,基于MMB和LABVIEW的电控柴油机标定系统,大连交通大学学报,2010
[27]吴志红,基于LabVIEW的汽车电子控制单元CCP标定系统设计,机械与电子,2008
[28]王伟达,汽车ASR系统ECU开发及其硬件在环测试,电子技术应用,2008
[29]ASAP Standard, Can Calibration Protocol Version 2.1, 1999
[30]林志华,基于CCP协议的电控发动机监控标定系统开发,汽车科技,2011
[31]王浩洁,基于LABVIEW的内燃机示功图模拟及燃烧分析系统开发,[硕士学位论文],四川;西南交通大学,2010
[32]催海龙,多缸发动机气缸压力采集与燃烧分析系统的研究,北京;北京工业大学,2003
[33]李秋风,内燃机燃烧分析测控系统开发,[硕士学位论文],天津;河北工业大学。
[34] NicosLadommatos. Engine Combustion Instrumentation and Dignostics , Society of Automotive Engineers,Inc, 2001
[35]AVL公司,AVL燃烧分析仪资料,2010
[36]FEV公司,FEV燃烧分析仪资料,2011
[37]奇石乐公司,奇石乐燃烧分析系统资料,2011
[38]田慧,栗保明,压电式压力传感器的测量与标定系统,电子元器件应用, 2008
[39]奇石乐扩展了其冲压力传感器系列,电机与控制应用, 2010
[40]奇石乐公司,奇石乐电荷放大器资料,2011
[41]长春光禹光学技术有限公司,光电编码器资料,2011
[42]北京阿尔泰科技有限公司,数据采集卡资料,2011
[43]美国国家仪器,labvIEW简介,2011
[44]邹喜红,压缩线法求动态上止点,小型内燃机与摩托车, 2003
[45]蒋德明,内燃机燃烧与排放学,西安,西安交通大学出版社,2001
[46]刘亮欣,黄佐华,蒋德明,天然气缸内直喷发动机燃烧循环变动特性研究,内燃机学报, 2005
[47]李兴虎,蒋德明,火花点火发动机压力循环变动的评价方法研究,内燃机学报, 2000
[48]侯圣智,HCCI汽油机混合燃烧及放热率计算模型,天津大学学报, 2009
[49]唐江,HCCI汽油机爆震控制研究,[硕士学位论文],天津;天津大学,2008
[50]黄希桥,严传俊,爆震频率对脉冲爆震发动机引射性能影响的试验,航空动力学报, 2008
[51]韩宇石,电控汽油机爆震信号分析与检测, [硕士学位论文],北京;北京工业大学, 2005
[52] Wu G, A real time statistical method for engine knock detection ,SAE2007-01-1507 [53]
[53] M.J. Kearney-Delphi,Knock signal conditioning using the discrete fourier transform and variable detection window length,SAE2007-01-1509
[54]徐帆,HCCI燃烧中爆震现象的研究及其控制策略,[硕士学位论文],北京;清华大学, 2011
[55]庄兵,彭飞舟,内燃机废气再循环(EGR)率评价方法分析,小型内燃机与摩托车, 2007
[56]郭鹏江,王天灵,利用文丘里管和VNT提高柴油机EGR率的研究,内燃机学报, 2009