甲醇均质压缩燃烧缸内取样及检测分析方法

为研究均质压燃条件下，缸内残余热废气中化学物质的成分及其对甲醇燃料低温氧化过程的影响，在Ricardo单缸四冲程发动机上利用改装的GDI直喷嘴建立了缸内取样系统，参照美国EPA大气中醛酮类物质的采集标准设计了样气采集系统，并进行了热废气状态下甲醇均质压缩燃烧低温氧化过程中间产物的缸内采样实验．利用2，4-二硝基苯肼（DNPH）衍生化法对样气中的醛酮类物质进行了富集，进而利用高效液相色谱技术对其进行了定性和定量分析，通过穿透实验、洗脱实验及标准曲线制作研究了低浓度醛酮类物质的采样和分析方法．实验结果表明，热废气中含有一定浓度的甲醛、乙醛、丙酮和丙烯酮等物质，且这些物质参与了甲醇最初的低温氧化过程．

In-Cylinder Gas Sampling and Detection Analysis Methods of Methanol Fueled Controlled Auto-Ignition Engines

In order to study the components of chemical substances in the hot residual gas and their effects on low- temperature oxidation process of methanol in a homogenous charge compression ignition engine, an in-cylinder gas sampling system and an aldehydes/ketones testing method were developed according to EPA standard by modifying a GDI injector on a Ricardo Hydra 4-stroke single cylinder gasoline engine. The in-cylinder sampling experiments during the methanol low-temperature combustion process were carried out. Aldehydes/ketones were collected with DNPH-silica cartridge and then analyzed qualitatively and quantitatively by high-performance liquid chromatography （HPLC）. The sampling and analysis methods were studied by penetrability experiment, elution rate experiment and standard curve performance. And the results showed that there are formaldehyde, acetaldehyde, acetone, propylene ketone, etc, in the hot residual gas, which have some influence on the low-temperature oxidation of methanol.