溶有甲烷煤油的稳态喷雾特性研究

研究了当溶有甲烷的煤油稳态通过直圆孔喷嘴时形成减压沸腾喷射的喷雾特性，试验使用了基于小角度向前散射理论的激光粒度分析仪和数码照相机，由溶解压力控制甲烷的溶解量，利用溶解气体释放产生的沸腾现象来改善雾化，分析了不同的甲烷溶解量、测量位置、喷射压力和喷嘴长径比对流量系数、喷雾形状和锥角、索特平均直径的影响．研究表明：对应于不同长径比的喷嘴，存在一个溶解度临界值，溶解度大于该值时促进雾化，小于该值时抑制雾化；甲烷的溶入使煤油喷雾锥角急剧增大；喷嘴内部气液两相流的性质对溶气油喷雾特性有很大的影响。

Investigation of Steady Spray Characteristics for Kerosene Containing Dissolved Methane

Spray characteristics of flashing injection were investigated for kerosene containing dissolved methane through straight-rounded-hole nozzles by use of a particle size analyzer based on the narrow-angle forward-scattering theory and a digital camera. The concentration of methane in kerosene was controlled by dissolving pressure, and the flashing phenomenon produced by separating dissolved methane was employed to improve atomization. The effects of concentration of dissolved methane, measurement position, injection pressure, and length-to-diameter ratio of nozzle (L/D), on discharge coefficient, spray pattern, spray angle, and Sauter mean diameters were examined. The result shows that for different L/D nozzles the corresponding critical values of methane concentration exist. When a concentration is above the critical value the atomization is improved, and below the critical value the atomization is suppressed. Moreover, fuel spray angles increase dramatically due to the methane dissolved. In addition, the properties of gas-liquid two-phase flow inside nozzles have great influence on the spray characteristics of fuel containing dissolved gas. .