燃用小桐子油柴油机怠速工况工作过程及循环波动

采用柴油、柴油-小桐子掺混油、小桐子油、高温小桐子油,在单缸水冷四冲程柴油机上进行了怠速工况试验,测录了多循环的瞬时气缸压力与高压油管燃油压力,对比分析了喷油与燃烧过程中各参数的循环波动。结果发现,怠速工况喷油过程中,喷油持续期的循环波动最明显,小桐子油的喷油始点滞后,喷油持续期长,喷油压力大,喷油过程的循环波动略大;怠速工况燃烧过程中,最大燃烧压力升高率和滞燃期的循环波动率最为明显,小桐子油滞燃期略短,燃烧压力升高率小,最高燃烧压力低,滞燃期和最大燃烧压力升高率的循环波动明显大于柴油;燃用小桐子油增大了原机的循环波动,怠速运转不如柴油稳定。

Analysis of working process and cycle variation of diesel engine fueled with curcas oil at idle condition

The idle conditions fueled with diesel,diesel-curcas mix oil,curcas oil and heated curcas oil are texted by a water-cooled four-stroke single cylinder diesel engine.The cycle variation of the parameters during injection and combustion process are analyzed with the multi-cycle cylinder instantaneous pressure and fuel pressure in the high pressure fuel pipe.It is found that the cycle variation of injection duration is most obviously in the injection process at idle condition.The ignition begin time of burning curcas oil is later,the injection duration is longer,the injection pressure is higher,the cycle variation is larger;the maximum pressure rising rate and cycle variation rate of ignition delay period are most obviously in the injection process at idle condition.The ignition delay period of burning curcas oil is shorter,the pressure rising rate is lower,the maximum combustion pressure is lower,the ignition delay period and maximum combustion pressure rising rate are significantly greater than diesel.Burning curcas oil increases the engine’s cycle variation at idle condition.