添加纳米铝的高密度悬浮燃料点火性能

Ignition Performance of High-Density Suspension Fuel of Adding Al NPs

为了探究含金属颗粒悬浮燃料的点火和燃烧特性,制备了含5%纳米铝颗粒(Al NPs)的HD-01和四环庚烷(QC)的高密度悬浮燃料,采用雾化激波管测试了两种悬浮燃料在不同压力和温度下的点火延时P,通过拟合计算得到了表观点火活化能,分析了悬浮燃料的点火燃烧机理,采用高速摄像机记录了点火燃烧的流场图像。结果表明,悬浮燃料静置4周后无颗粒聚沉现象;在0.05 MPa和0.1 MPa下、1450 K和1750 K内,Al NPs可使HD-01和QC燃料的点火延时缩短约50%,表观点火活化能由161.4 k J·mol^(^(-1))和120.3 k J·mol^(-1)分别降低至156.5 k J·mol^(-1)和112.8 k J·mol^(-1);推测燃烧机理为铝原子优先与O2反应生成O自由基,进而加速燃烧反应。此外,Al NPs能够完全燃烧并促进燃料燃烧过程中的能量释放。

To study the ignition and combustion characteristics of suspended fuel containing metal particles,two kinds of high-density suspension fuels of HD-01 and quadricyclane(QC)with 5%aluminum nanoparticles(Al NPs)were prepared.The ignition delay of two kinds of suspended fuels at different pressure and temperature was measured by atomization shock tube.The apparent activation energy of ignition was obtained by fitting and calculating.The ignition and combustion mechanism of the suspension fuel were analyzed.The flow field images of ignition and combustion were recorded by high-speed camera.Results show that the suspended fuel can stand after 4 weeks without particle aggregation phenomenon;in the range of 0.05 MPa and 0.1 MPa,1450 K and 1750 K,Al NPs can make the ignition delay of HD-01 and QC fuel shorten by about 50%and the apparent ignition activation energy reduce from 161.4 kJ·mol-1 and 120.3 kJ·mol-1 to 156.5 kJ·mol-1 and 112.8 kJ·mol-1,respectively;Inferring that the combustion mechanism as that aluminum atoms preferentially react with O 2 to produce O radicals,thereby accelerating the combustion reaction.In addition,Al NPs can completely burn and promote the energy release during fuel combustion.