【作者】 靖海国；

【导师】 宋恩哲；

【作者基本信息】 哈尔滨工程大学 ， 动力机械及工程， 2011， 硕士

【摘要】 能源危机和环境问题使得天然气发动机的研究成为发动机技术的一个重要发展方向。其中用柴油作引燃燃料的柴油/CNG双燃料发动机以其改装方便、经济性好、热效率高等优点日益受到重视。本文选用船用柴油机2135G改装成双燃料发动机；以MC9S12XDP512单片机为核心设计了电路板用来处理发动机状态参数信号、控制步进电机以及和监控界面进行通讯。基于LabVIEW软件,本文设计了双燃料发动机监控系统,实现了柴油机转速显示、爆震信号显示、步进电机控制等功能。谐振进气系统是提高发动机的充气系数、改善其动力性能的一种行之有效的方法。根据谐振理论,本文设计了一套谐振腔进气系统,在双燃料发动机试验台上研究了谐振腔体积对发动机动力性能的影响。试验表明,谐振进气系统能够增加进气量,为CNG单一燃料发动机功率提升做了技术储备。本文研究了基础油量对双燃料发动机性能的影响。试验表明,在相同负荷下,基础油量增加,CO排放减少,NOx排放增加,在中低负荷时尤为明显。在高负荷时改变基础油量对CO和NOx的排放影响变小。本文研究了喷油提前角对双燃料发动机性能的影响。试验表明,当供油提前角增加时,NOx排放升高,CO的变化不明显,因此增大供油提前角对降低NO、排放不利。若供油提前角过小,则会出现严重的后燃现象,爆震值增加。更多还原

【Abstract】 The energy crisis and environmental problems make natural gas engines become an important engine technology development direction. The diesel/CNG dual fuel engine causes more and more attention for its refitting convenient, economical and high thermal efficiency.We configure a dual fuel engine by using a marine diesel engine 2135G;design a circuit board to handle engine state parameter signals、control stepping motor and communicate with monitoring interface by using a MC9S12XDP512 singlechip. We design control system based on LabVIEW software to display the diesel engine speed, knock signal and control the stepping motor.Resonant air intake system is a kind of effective method to improve the air intake coefficient of engine and the dynamic performance. We design a resonant air intake system according to the resonance theory and study the influence of the resonator to the engine dynamic property. Test shows that resonant air intake system can increase air intake flow which does technical reserves for CNG single fuel engine power increasing.We study the influence of base oil amount to the dual fuel engine performance. Test shows that CO emission decreases while NOx emission increases with the increasing of base oil amount under the same load.and it is more apparent under small and middle load.We also study the influence of fuel supply advance angle to the dual fuel engine performance. Test shows that NOx emission increases while CO emission does not change significantly with the increasing of fuel supply advance angle. So it is not beneficial to NOx emission by increasing the fuel supply advance angle. But it will appear to be a serious afterburning phenomenon and the detonation value will increase if the fuel supply advance angle is too small.更多还原