准确模拟喷雾是提高缸内模拟准确性的关键,为了使模拟喷雾与试验喷雾更加一致,需要根据试验喷雾贯穿距及粒径对模拟喷雾进行标定.使用AVL FIRE软件建立定容弹及喷雾数值模型,对处于不同喷射工况(喷射压力、环境压力、油温)下的喷雾进行数值模拟,根据试验喷雾的贯穿距及喷嘴下方30 mm平面处SMD对模拟喷雾进行标定,并对不同喷射工况的标定参数选择进行探讨.结果表明:为了同时满足贯穿距和粒径的标定要求,需要根据工况参数对标定参数进行调整;对于本研究中的GDI喷油器,喷射压力10 MPa时使用KH-RT模型的模拟结果与试验值匹配较好,5 MPa时使用Huh-Gosman模型匹配更好;在喷射压力、环境压力和环境温度相同的条件下,高油温和低油温工况可以用同一套参数满足标定要求.%Simulating the in-cylinder spray correctly is the key step to improve the in-cylinder simulation.It is usually necessary to calibrate simulated spray according to measured spray penetration and droplet size in order to achieve the uniformity between the simulated spray and the test spray.The spray simulation under different conditions of injection pressure, ambient pressure and fuel temperature was carried out with the numerical model of constant volume bomb and spray established by AVL FIRE software.The simulated spray was calibrated according to the penetration of test spray and the SMD at the plane of 30 mm below the nozzle and the calibration parameters of different injection conditions were discussed.The results show that spray simulation parameters need to be adjusted under various conditions.The simulation results of KH-RT and Huh-Gosman breakup model are in good agreement with the experimental values when their respective injection pressure is 10 MPa and 5 MPa.Besides, the calibration parameters are little influenced by fuel temperature.
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