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美国伊利诺伊大学、清华大学千人计划教授讲座

时间 : 2016年11月18日 08时30分

地点 : 动力工程学院303

主办单位 : 重庆大学工程学部

协办单位 : 重庆大学动力工程学院,低品位能源利用技术及系统教育部重点实验室

Low-Temperature Combustion of Diesel and Bio-fuels for Diesel Engines

主讲人 : Prof.Chia-fon Lee

Clean combustion of diesel and biodiesel within a small-bore optical diesel engine will be the focus of this presentation. Small-bore High-Speed Direct Injection (HSDI) diesel engines are becoming attractive candidates for light duty vehicles due to their superior thermal efficiency and less greenhouse gas exhaust. New combustion modes, e.g. Homogeneous Charge Compression Ignition (HCCI) combustion, provide a unique approach for emission reduction. However, the application of HCCI combustion mode is limited in low load conditions. In this talk, a clean combustion mode, namely low temperature combustion, will be presented. Experimental investigations of low temperature combustion were carried out in an optically accessible diesel engine. The air-fuel mixing process, combustion, and late cycle soot were visualized through the application of advanced non-intrusive diagnostic techniques including Mie-scattering, Laser Induced Exciplex Fluorescence, natural flame luminosity imaging, time-resolved 2-D light extinction method, and so forth. The NOx emission was measured in the exhaust pipe. It is shown that by controlling the in-cylinder air temperature around 800K-950K at the start of main injection low temperature combustion can be achieved with low soot and low NOx emissions under an operation load up to 7 bar IMEP. Results of low temperature combustion with narrow angle direct injection technique will be demonstrated. Some examples of low temperature combustion of biodiesel, bio-butanol and diesel blends will also be discussed. Results show that low temperature combustion with bio-fuels can simultaneously reduce soot and NOx emissions. The mechanism for low temperature combustion is analyzed and addressed. Future research plans concerning sustainable and clean energy strategies will be outlined.

In additional to the HSDI research, several studies in the FAST Lab will be briefly introduced including optical port fuel-injection/gasoline direct-injection engines, spray/wall impingement, an optical direct injection of natural gas engine, diesel sprays in a high pressure cold chamber and in a high temperature/pressure hot bomb, droplet studies in a steady flow spray chamber, a diesel reformer for a solid oxide fuel cell, and catalytic micro-combustion. The laser diagnostics involved are multicomponent planar laser-induced exciplex fluorescence, planar laser-induced fluorescence, phase/doppler particle analysis, forward scattering drop sizing, planar drop size measurement, laser-induced incandescence, nature flame emission, high speed digital video plus high frequency/energy light source or back-lit photograph, Mie scattering, two-color infrared pyrometry, light extinction, and forward illumination light extinction. The related multidimensional modeling of the spray and engine processes will also be introduced.



主讲人简介:

Prof.Chia-fon Lee,1982年本科毕业于台湾中央大学,1989年获美国休斯顿大学硕士学位,1995年获美国普林斯顿大学博士学位。1995年起任美国伊利诺伊大学香槟分校助理教授,副教授和教授。2010-2014年在清华大学任燃烧能源中心副主任,汽车系教授,千人计划讲席教授。

主要从事燃油喷雾、发动机燃烧与排放等领域的研究工作。通过计算机模拟技术和激光诊断测量技术,对发动机喷雾和液体燃料蒸发过程、低温燃烧过程、生物代用燃料燃烧、低温燃烧排放、颗粒物和湍流的交互作用等方向进行了大量的实验研究和新模型建立发展工作。研究工作在发动机设计改进、缩短开发周期、提高发动机经济性及降低排放等方面取得显著效果。在能源和环境领域的开拓性研究得到了广泛的认可,于2005年被任命为美国能源部先进车用生物燃料发动机燃烧中心主任,负责多项美国能源部等机构的科研项目。又现任美国汽车工程师协会高级会员(SAE Fellow)、喷雾与雾化刊物编委等职,并曾担任国际燃烧学会评审委员会委员(2001年~2009年),第15、16届液体雾化喷雾系统年会会议主席。

围绕降低柴油机燃烧过程中最难解决的碳烟和氮氧化物的排放进行了大量的研究工作。发展了一种更加便利的缸内碳烟量的在线实时诊断方法;所提出的计算模型有效的应用到发动机的设计过程中,减少了大量的样机测试过程。在具有实际应用意义的主题中,探索了有关基础科学的研究对象,进行了深入的研究。发表高层次期刊论文202篇,会议论文139篇,和一本书的章节,各种应邀报告共60余次。李佳峰教授在多组分燃料蒸发研究;闪蒸和微爆条件下雾化研究;喷雾撞壁研究;柴油机燃用柴油、生物柴油、柴油及含氧添加剂等燃料的低温燃烧研究等方面取得了国际领先的研究成果。


作者 : 工程学部 吴瑶

责任编辑 : 陈青

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