进气氧气体积分数对搭载制氢机的内燃机性能影响的试验研究

Effect of Intake Oxygen Volume Fraction on Engine Performance With On-board Hydrogen Generator

为了探究搭载制氢机后进气氧气体积分数对内燃机性能的影响,对北汽A151内燃机进行了改造,在节气门后加装了氧气喷嘴引入氧气,开发了一套电控氧气喷射系统实现进气氧气体积分数的精准控制.试验选取汽车在市区道路运行中4个常见的内燃机工况,分别为:转速1 500 r/min,进气道绝对压力42 k Pa;转速1 500 r/min,进气道绝对压力68 k Pa;转速2 000 r/min,进气道绝对压力42 k Pa;转速2 000 r/min,进气道绝对压力68 k Pa.通过控制氧气喷射量改变进气氧气体积分数,研究了不同进气氧气体积分数对内燃机动力性、经济性、排放性及燃烧特性的影响.研究结果表明,增加进气氧气体积分数能够强化燃烧,提高内燃机的动力性,转矩最多可提高50%;部分工况下经济性得到改善,比油耗最多可降低18. 6%; HC排放降低63. 15%;但在全部工况下NOx排放均有所升高.

To explore the effects of changing intake oxygen volume fraction after installing on-board hydrogen generator,an A151 engine manufactured by BAIC Group was modified. Oxygen injectors were placed in the rear of throttle valves. A self-developed electronic control system was used to control the intake oxygen volume fraction. The experiments were carried out under 1 500 r/min and 42 kPa,1 500 r/min and 68 kPa,2 000 r/min and 42 kPa,and 2 000 r/min and 68 k Pa operating conditions,respectively. In this paper,the combustion,dynamic,economy and emissions performances of the engine installed on-board hydrogen generator with different intake oxygen volume fractions were studied.Experimental results show that the increase of the intake oxygen volume fraction can enhance combustion,and improve the power of the engine. The torque increases at most 50%. The economy is improved under particular conditions,and the fuel consumption is reduced at most 18. 6%. HC emissions decrease at most 63. 15%,while the NOxemissions increase under all conditions.