预混合压燃式天然气发动机燃烧性能的初步试验研究

对影响单一燃料天然气发动机压缩着火运转范围和排放特性的相关因素进行了试验研究．设计开发的新型燃烧系统采用球形涡流室式燃烧室配以电控天然气复合供气系统，通过台架试验，研究了不同的天然气供气方式、涡流室结构参数、进气空气加热温度及陶瓷电热塞温度对着火燃烧及排放的影响．试验结果表明，天然气低压进气道供气方式有利于天然气的压缩着火；在一定范围内适当增加涡流室与主室通道尺寸，有利于缓解预混合压燃的敲缸现象；辅助加热温度受到敲缸与部分燃烧现象的制约，应当精确控制．

Experimental Investigation on Combustion Characteristics of Premixed Charge Compression Ignition CNG Engine

The factors which affect the operation range and emission characteristics are explored with experiments on a premixed charge compression ignition CNG (compressed nature gas) engine.The designed combustion system consists of divided chambers and electrical-controlled compound CNG supplement system.The effect of CNG supplement method divid- ed chamber geometry,and the heating temperature on combustion and emission arc studied.The results show that CNG supplement with low pressure injection in intake port is favorable for compression ignition;moderately increasing the pas- sage size between auxiliary and main chambers can help relieve knock in premixed charge compression ignition operation; heating temperature for intake air should be regulated precisely with the limitation of knock and partly combustion.