本文主要研究内容
作者林佳眉（2019）在《汽油机废气再循环下的稀薄燃烧空燃比控制》一文中研究指出：面对日益严苛的排放法规和石油能源短缺的危机,稀薄燃烧技术所具备的高效节油和降低排放污染的优势使其受到广泛的研究和关注。稀薄燃烧技术的关键是使发动机运行在高空燃比下,空燃比的提高,能够使缸内混合气体燃烧更加充分,提高发动机热效率,节约燃油,同时,减少部分发动机尾气的排放。NOx排放的增加是稀薄燃烧技术难以推广和应用的原因之一。为了解决NOx的排放问题,本文提出废气再循环技术(EGR)与稀薄燃烧技术相结合的技术路线。废气再循环技术通过将废气引入气缸,降低燃烧温度,破坏缸内富氧条件,从而抑制NOx的生成。废气再循环技术与稀薄燃烧技术均对使用范围有着严格的要求,因此,根据工况合理选择EGR率和稀燃空燃比能够使发动机在运行过程中保证动力性的前提下,同时兼顾经济性和排放性。本文研究了稀薄燃烧与废气再循环的协同作用,并对空燃比进行了精准跟踪,给出了不同工况下的仿真实验验证。首先,对含有废气循环的气路特殊结构进行建模。考虑废气的引入带来进气歧管内压力和温度的变化,建立了“双态”模型来描述进气歧管的动态特性。为了提高气缸进气量的精确性,考虑发动机容积效率等因素带来的偏差,设计了高增益气缸进气量观测器。此时得到的气缸进气量中包含废气部分,根据能量守恒定律计算得出进入气缸的新鲜空气量,可用于空燃比控制的计算与推导。通过高精度仿真软件GT-POWER与Simulink的联合仿真,对所建立的模型进行了仿真验证,验证结果表明,模型精度较好,可以反映发动机的性能,为后文的空燃比跟踪控制器设计奠定了基础。其次,通过分析稀薄燃烧技术和废气再循环技术对油耗和排放的影响,发现二者协同作用能够使发动机性能提升。选取节气门开度、发动机转速、气缸进气量、EGR率和空燃比作为输入量,选取发动机的有效燃油消耗率、氮氧化物NOx和碳氢化合物HC的排放作为输出量,利用BP神经网络建立了非线性预测模型,基于非线性模型预测控制方法设计了优化控制方案,对系统的状态和控制输入进行了约束限制,以燃油消耗率、NOx和HC的排放最小为性能指标,优化出不同工况下的EGR率和理想稀燃空燃比值。通过仿真实验,与当量空燃比进行对比,稀燃下的发动机排放和油耗均有所降低,满足排放要求,改善发动机的经济性和排放性,验证了所提出的优化方案的有效性。最后,分析了油膜湿壁效应的影响,设计了油膜蒸发模型,得到喷油嘴的喷油量与缸内燃油量的关系,用于空燃比控制系统的推导。考虑到工程应用的可行性,基于三步非线性控制方法,设计了空燃比跟踪控制器。本文对控制器的性能进行了仿真验证,对于当量空燃比,稳态工况和瞬态工况均能实现良好的跟踪。此外,将优化得到的理想稀燃空燃比作为期望值,控制器也能对给定期望值跟踪,具有较好的控制效果,验证了控制算法的准确性和可靠性。
Abstract
mian dui ri yi yan ke de pai fang fa gui he dan you neng yuan duan que de wei ji ,xi bao ran shao ji shu suo ju bei de gao xiao jie you he jiang di pai fang wu ran de you shi shi ji shou dao an fan de yan jiu he guan zhu 。xi bao ran shao ji shu de guan jian shi shi fa dong ji yun hang zai gao kong ran bi xia ,kong ran bi de di gao ,neng gou shi gang nei hun ge qi ti ran shao geng jia chong fen ,di gao fa dong ji re xiao lv ,jie yao ran you ,tong shi ,jian shao bu fen fa dong ji wei qi de pai fang 。NOxpai fang de zeng jia shi xi bao ran shao ji shu nan yi tui an he ying yong de yuan yin zhi yi 。wei le jie jue NOxde pai fang wen ti ,ben wen di chu fei qi zai xun huan ji shu (EGR)yu xi bao ran shao ji shu xiang jie ge de ji shu lu xian 。fei qi zai xun huan ji shu tong guo jiang fei qi yin ru qi gang ,jiang di ran shao wen du ,po huai gang nei fu yang tiao jian ,cong er yi zhi NOxde sheng cheng 。fei qi zai xun huan ji shu yu xi bao ran shao ji shu jun dui shi yong fan wei you zhao yan ge de yao qiu ,yin ci ,gen ju gong kuang ge li shua ze EGRlv he xi ran kong ran bi neng gou shi fa dong ji zai yun hang guo cheng zhong bao zheng dong li xing de qian di xia ,tong shi jian gu jing ji xing he pai fang xing 。ben wen yan jiu le xi bao ran shao yu fei qi zai xun huan de xie tong zuo yong ,bing dui kong ran bi jin hang le jing zhun gen zong ,gei chu le bu tong gong kuang xia de fang zhen shi yan yan zheng 。shou xian ,dui han you fei qi xun huan de qi lu te shu jie gou jin hang jian mo 。kao lv fei qi de yin ru dai lai jin qi qi guan nei ya li he wen du de bian hua ,jian li le “shuang tai ”mo xing lai miao shu jin qi qi guan de dong tai te xing 。wei le di gao qi gang jin qi liang de jing que xing ,kao lv fa dong ji rong ji xiao lv deng yin su dai lai de pian cha ,she ji le gao zeng yi qi gang jin qi liang guan ce qi 。ci shi de dao de qi gang jin qi liang zhong bao han fei qi bu fen ,gen ju neng liang shou heng ding lv ji suan de chu jin ru qi gang de xin xian kong qi liang ,ke yong yu kong ran bi kong zhi de ji suan yu tui dao 。tong guo gao jing du fang zhen ruan jian GT-POWERyu Simulinkde lian ge fang zhen ,dui suo jian li de mo xing jin hang le fang zhen yan zheng ,yan zheng jie guo biao ming ,mo xing jing du jiao hao ,ke yi fan ying fa dong ji de xing neng ,wei hou wen de kong ran bi gen zong kong zhi qi she ji dian ding le ji chu 。ji ci ,tong guo fen xi xi bao ran shao ji shu he fei qi zai xun huan ji shu dui you hao he pai fang de ying xiang ,fa xian er zhe xie tong zuo yong neng gou shi fa dong ji xing neng di sheng 。shua qu jie qi men kai du 、fa dong ji zhuai su 、qi gang jin qi liang 、EGRlv he kong ran bi zuo wei shu ru liang ,shua qu fa dong ji de you xiao ran you xiao hao lv 、dan yang hua wu NOxhe tan qing hua ge wu HCde pai fang zuo wei shu chu liang ,li yong BPshen jing wang lao jian li le fei xian xing yu ce mo xing ,ji yu fei xian xing mo xing yu ce kong zhi fang fa she ji le you hua kong zhi fang an ,dui ji tong de zhuang tai he kong zhi shu ru jin hang le yao shu xian zhi ,yi ran you xiao hao lv 、NOxhe HCde pai fang zui xiao wei xing neng zhi biao ,you hua chu bu tong gong kuang xia de EGRlv he li xiang xi ran kong ran bi zhi 。tong guo fang zhen shi yan ,yu dang liang kong ran bi jin hang dui bi ,xi ran xia de fa dong ji pai fang he you hao jun you suo jiang di ,man zu pai fang yao qiu ,gai shan fa dong ji de jing ji xing he pai fang xing ,yan zheng le suo di chu de you hua fang an de you xiao xing 。zui hou ,fen xi le you mo shi bi xiao ying de ying xiang ,she ji le you mo zheng fa mo xing ,de dao pen you zui de pen you liang yu gang nei ran you liang de guan ji ,yong yu kong ran bi kong zhi ji tong de tui dao 。kao lv dao gong cheng ying yong de ke hang xing ,ji yu san bu fei xian xing kong zhi fang fa ,she ji le kong ran bi gen zong kong zhi qi 。ben wen dui kong zhi qi de xing neng jin hang le fang zhen yan zheng ,dui yu dang liang kong ran bi ,wen tai gong kuang he shun tai gong kuang jun neng shi xian liang hao de gen zong 。ci wai ,jiang you hua de dao de li xiang xi ran kong ran bi zuo wei ji wang zhi ,kong zhi qi ye neng dui gei ding ji wang zhi gen zong ,ju you jiao hao de kong zhi xiao guo ,yan zheng le kong zhi suan fa de zhun que xing he ke kao xing 。
论文参考文献
论文详细介绍
论文作者分别是来自吉林大学的林佳眉，发表于刊物吉林大学2019-06-25论文，是一篇关于空燃比控制论文,稀薄燃烧汽油机论文,废气再循环论文,非线性模型预测控制论文,三步非线性控制论文,吉林大学2019-06-25论文的文章。本文可供学术参考使用，各位学者可以免费参考阅读下载，文章观点不代表本站观点，资料来自吉林大学2019-06-25论文网站，若本站收录的文献无意侵犯了您的著作版权，请联系我们删除。
标签：空燃比控制论文; 稀薄燃烧汽油机论文; 废气再循环论文; 非线性模型预测控制论文; 三步非线性控制论文; 吉林大学2019-06-25论文;