摘要
对一台增压、火花点燃液化天然气(LNG)发动机的进气系统加装一套补气装置并进行试验,连续记录补气过程中进气压力、空燃比、燃料质量流量和缸内动态压力等体现缸内燃烧及热功转化过程的瞬变参数。通过分析实测燃烧放热率(ROHR),揭示了瞬变状态下发动机空燃比、燃料质量流量和进气压力等运行参数对燃烧特征参数的影响,指出燃烧推迟、失火和平均指示压力(IMEP)波动等燃烧失常现象,并得出这些现象的产生原因。研究结果表明:无论是稳态工况还是瞬态工况,LNG发动机的燃烧过程主要由过量空气系数决定。
The engine related parameters, such as intake manifold pressure, air/fuel ratio（AFR）, fuel mass flow-rate, as well as dynamic in-cylinder pressure traces, were measured on a turbocharged LNG engine with external air injection according to the transient procedure. During the transient and ramped modal testing, the engine experienced not only abrupt change of boost pressure and AFR, but also rapid engine load change. The changes in the in-cylinder combustion process during the transient test cycle, which were rarely revealed before, were illustrated with the rate of heat release（ROHR） characteristics. The influence of operation parameters on the combustion process under transient conditions was examined and discussed. Moreover, the existence of abnormal combustion such as late combustion, misfiring and severe variation of IMEP, etc. was pointed out. The possible cause of those abnormal combustion phenomena was also analyzed. Results show that under steady state and transient conditions, the LNG engine combustion process is dominated by the relative AFR.
作者
张孔明
梁世希
金则兵
张帆
王科
刘敬平
ZHANG Kongming LIANG Shixi JIN Zebing ZHANG Fan WANG Ke LIU Jingping(Beijing Green Academy of Gas Application Technology,Beijing 100101, China Research Center for Advanced Powertrain Technologies, Hunan University,Changsha 410082,China)
出处
《内燃机工程》
EI
CAS
CSCD
北大核心
2017年第1期81-87,共7页
Chinese Internal Combustion Engine Engineering
基金
国家"九七三"重点基础研究发展计划项目(2011CB707201)
