【作者】 王建军；

【导师】 钱叶剑；

【作者基本信息】 合肥工业大学 ， 动力工程（专业学位）， 2014， 硕士

【摘要】 资源枯竭和环境污染已成为当今世界所面临的两个难题，它们正日益影响着人类的生存和发展。随着现代汽车工业的发展，汽车的排放已成为一个主要的大气污染源，而且越来越多的石化资源被汽车所消耗。因此寻找可再生车用绿色替代能源和开发新型燃烧方式已成为当今研究的热点。CFD软件现已广泛应用于发动机缸内工作过程的模拟，相比于台架实验，也有较多的优势。丁醇作为第二代可开发燃料，在发动机上有很大的应用潜力。本文在CFD软件中以SQR272汽油机为原型建立一个缸内直喷点燃式发动机模型，并耦合正丁醇和汽油的简化燃烧机理，理论研究了丁醇、汽油及丁醇汽油混合燃料在缸内直喷发动机上不同EGR率时的燃烧过程及排放特性。理论计算结果表明：在缸内直喷点燃式发动机燃用丁醇、汽油及丁醇汽油混合燃料时，不同EGR率下，缸内峰值温度和压力及NOX排放曲线随点火时刻的延迟均呈先升后降的变化趋势，而随着EGR率的增大，缸内峰值温度和压力及NOX排放最大值对应的点火时刻均有所推迟；在缸内直喷点燃式发动机燃用丁醇、汽油、B10及B20时，在不同EGR率下，缸内峰值温度和压力及NOX排放曲线随当量比的增加也均呈先升后降的变化趋势，而燃用B30时缸内峰值温度和压力及NOX排放曲线随当量比的增加呈上升趋势，EGR率的变大时，缸内峰值温度和压力及NOX排放均有一定的下降。更多还原

【Abstract】 Resource depletion and environmental pollution have become two challenges facingthe world today, and they are increasingly affecting the survival and development ofhuman beings. With the development of modern automobile industry, emissions ofautomobile pollutants have become one of the major air pollution sources; meanwhilea growing number of oil resources are consumed. Therefore searching for therenewable clean alternative energy and developing new combustion mode havebecome the focus of current research.CFD software has been widely applied in the simulation of working process ofengine cylinder. Compared with the bench test, it has more advantages. As the secondgeneration of renewable alternative fuels, butanol has great potential for application inengine. Based on the prototype of the CFD software to SQR272gasoline engine, wehave established a SID（ISpark Ignition Direct Injection）model. On the different EGRrate, we will import the simple coupling mechanism of n-butanol and gasoline in thismodel to study the combustion process and emission characteristics of butanol,gasoline and alcohol-gasoline blended fuel.By analyzing the data, we find out that: in SIDI engine, when we fuel with butanol,gasoline and butanol gasoline blended fuel on different EGR rate, the peak cylindertemperature and pressure and NOXemissions curve with the ignition delay time show atrend of increased first and then decreased. And with the increasing of EGR rate, peakcylinder pressure and temperature and the maximum of NOXemissions correspondingto the ignition timing will be postponed. In SIDI engine, when we fueled with butanol,gasoline B10and B20on different EGR rate, the peak cylinder temperature andpressure and NOXemissions curve with the equivalence ratio also show a trend ofincreasing first and then decreasing, but B30shows a trend of increasing. And with theincreasing of EGR rate, peak cylinder pressure and temperature and NOXemissionshave a certain decline.更多还原