In this paper, the numerical simulation of the diesel and gasoline fuels injection in a constant volume chamber and in a cylinder under the operating conditions of a compression ignition (CI) engine is conducted. The simulation results are compared with the experimental data which derived from fast imaging techniques. In order to check out the possibility of using gasoline instead of diesel to increase the volumetric efficiency of the CI engine, the spray characteristics of the gasoline and diesel with injection pressures of 40 and 80 MPa, as well as temperatures of 243, 273 and 313 K, under cold start condition is investigated. The results show that under the same conditions, the vapor penetration length for the two fuels is approximately equal and due to the lower volatility of the diesel fuel, its liquid penetration length in 40 and 80 MPa injection pressures was found to be 7 and 9 mm higher than gasoline, respectively. In addition, the reduction in fuel temperature from 313 K to 243 K leads an increase in the penetration of gasoline and diesel liquids by 12 and 10 mm, respectively. Finally, the decrease in the evaporation rate causes a non-homogeneous mixture and results an increase in the unburned hydrocarbons and emissions.

中文翻译：

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直喷压缩点火发动机中柴油和汽油喷射的实验和计算研究

在本文中，在压缩点火（CI）发动机的工作条件下，对在恒定容积的室内和气缸中喷射的柴油和汽油燃料进行了数值模拟。仿真结果与快速成像技术得出的实验数据进行了比较。为了检验使用汽油代替柴油来提高CI发动机的容积效率的可能性，喷射压力为40和80 MPa，温度为243、273和313时，汽油和柴油的喷雾特性研究了冷启动条件下的K。结果表明，在相同条件下，两种燃料的蒸汽渗透长度大致相等，并且由于柴油燃料的挥发性较低，在40和80 MPa的注射压力下，其液体渗透长度分别比汽油高7和9毫米。此外，燃油温度从313 K降低到243 K，使汽油和柴油液体的渗透率分别增加了12和10 mm。最后，蒸发速率的降低导致混合物不均匀，并导致未燃烧的碳氢化合物和排放物增加。