中文摘要：

为深入认识多孔介质发动机中均匀混合气的形成，用改进的KIVA-3V详细模拟了伞喷油雾与热多孔介质之间的相互作用．在KIVA-3V中增加了油滴碰撞热多孔介质壁面的碰撞模型、传热模型．为检测数值模型的合理性，在Senda等人的实验条件下进行了数值计算．油束碰壁后油滴和油蒸气分布的数值计算结果与实验结果吻合较好．在简化多孔介质结构的基础上和不同的环境压力及喷雾锥角时，模拟了伞喷油雾与热多孔介质的碰撞过程．计算结果表明，伞喷油雾的喷雾锥角及空间压力对油滴在多孔介质中的分布有着很大的影响，在多孔介质厚度一定时，通过调节这些参数，能够形成均匀混合气．

英文摘要：

To conduct a fundamental study on mixture formation in porous medium engine, a numerical simulation of the interac- tion between umbrella spray and a hot porous medium was made. The improved KIVA-3V cede used here was incorporated into the impingement model and the heat transfer model for simulating the process of fuel droplets impinging on a heated wall. In order to validate the reasonability of the impingement model and of the heat transfer model, an evaporating fuel spray impingement on a hot plane surface was simulated under the experimental conditions designed by Senda et al. The numerical results were in good agreemerit with the experimental data for spray radius in liquid and vapor phases. With the structure of the hot porous medium simplified, the interaction between umbrella spray and the porous medium was simulated in detail. The computational results show that changing ambient pressure and spray cone angle can directly affect the distribution of droplets in porous medium. With the thickness of the porous medium fixed, the homogeneous mixture in porous medium may be obtained by adjusting these parameters.