内燃机工程2025，Vol.46Issue(3)：27-38,12.DOI:10.13949/j.cnki.nrjgc.2025.03.004
空气辅助喷射系统喷雾过程与雾化机制的数值模拟
Numerical Simulation on the Spray Process and Atomization Mechanism of an Air-Assisted Injection System
摘要
Abstract
To deeply study the spray process and atomization mechanisms caused by the gas-liquid interaction in an air-assisted injection system,a numerical model was established based on the Eulerian-Lagrangian approach.The model includes a complete air-assisted injector and a constant-volume environment,with a more precise and universal spray model setup proposed.The spray process is divided into the fuel-air mixing stage and the mixture injection stage.The surface break-up process of the fuel jet in the fuel-air mixing stage,as well as the rebound,splash,and adhesion behaviors of droplets with the wall were qualitatively analyzed.The critical role of the mixing chamber design in the gas-liquid mixing efficiency and intake stability was clarified.The results from the mixture injection stage indicate that the average droplet diameter inside the constant-volume environment is about 6 μm,and droplets with an average diameter of 20～30 μm exist at the Laval nozzle exit.Furthermore,further research on the atomization mechanism reveals that a small number of droplets with diameters greater than 50 μm also exist in the exit region,and these droplets originate from the separation of the film on the outer wall.The formation mechanism of vortex rings was revealed in the study.The near-field vortex ring is determined by the geometry of the Laval nozzle,and the far-field vortex ring is generated by the high-speed air disturbing the stagnant nitrogen gas through viscous forces.Finally,an analysis of the film mass variation on each wall of the air-assisted injector indicates a large amount of film that is difficult to strip from the upper inner wall,which could lead to fuel accumulation issues during cold start.关键词
空气辅助喷射系统/欧拉-拉格朗日法/油膜分离与剥离/涡环/油膜质量Key words
air-assisted injection system/Eulerian-Lagrangian approach/film separation and stripping/vortex ring/film mass分类
能源与动力引用本文复制引用
邱豪佶,黄云龙,何志霞,钟汶君..空气辅助喷射系统喷雾过程与雾化机制的数值模拟[J].内燃机工程,2025,46(3):27-38,12.基金项目
国家自然科学基金项目(52376113)National Natural Science Foundation of China(52376113) （52376113）
