To study the atomization characteristics of a liquid–centered gas–liquid pintle injector under periodic operating conditions, the gas–liquid interaction, breakup dynamics and spray morphology of the pintle element are simulated based on the three–dimensional volume of fluid to discrete particle model (VOF to DPM) and octree adaptive mesh refinement (AMR) when the liquid jet velocity changes according to sinusoidal law. The simulation results show that: (1) The fragmentation mechanism of liquid jets under periodic operating conditions can be divided into column breakup caused by Rayleigh–Taylor (R–T) instability and surface breakup caused by Kelvin–Helmholtz (K–H) instability. (2) Under specific operating conditions, the “flow interruption” phenomenon occurs. When the variation amplitude of liquid jet velocity increases from 3.125 m/s to 12.5 m/s, the occurrence time of “flow interruption” decreases by 10.46%, the spread angle increases by 36.79%, and the dimensionless length of liquid jet before “interruption point” decreases by 59.89%. (3) Additional disturbance waves occur due to the klystron effect. The gas–liquid interaction increases at the location where liquid flow accumulates. When the variation frequency of liquid jet velocity increases from 8 kHz to 16 kHz, the reduction amplitude of ${\lambda }_1$, ${\lambda }_2$ and ${\lambda }_3$ is all around 50%.

为研究液心气液枢轴式喷油器在周期性工况下的雾化特性，基于三维体积流体到离散粒子模型，模拟了枢轴元件的气液相互作用、破碎动力学和喷雾形貌(VOF 到 DPM) 和八叉树自适应网格细化 (AMR) 当液体射流速度根据正弦规律变化时。仿真结果表明：（1）周期性工况下液体射流的破碎机制可分为瑞利-泰勒（R-T）不稳定性引起的柱破碎和开尔文-亥姆霍兹（K-H）不稳定性引起的表面破碎. (2)在特定的运行条件下，会出现“断流”现象。当液体射流速度的变化幅度从3.125 m/s增加到12.5 m/s时，“流动中断”发生时间减少10.46%，扩散角增加36.79%，“中断点”前液体射流无量纲长度减少59.89%。(3) 由于速调管效应而产生附加干扰波。在液流聚集的位置，气液相互作用增加。当液体射流速度的变化频率从 8 kHz 增加到 16 kHz 时，${\lambda }_{\mathrm{1个}}$,${\lambda }_{\mathrm{2个}}$和${\lambda }_{\mathrm{3个}}$都在50%左右。