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为研究多孔发射药受冲击载荷的力学响应过程及几何参数变化对药粒力学性能的影响，采用ANSYS/LS‑DYNA有限元软件建立了七孔、十九孔发射药计算模型，模拟药粒在冲击载荷下的受力情况，然后建立单孔发射药模型，长径比为1∶1、2∶1的七孔、十九孔发射药和花边形七孔、十九孔发射药模型，研究孔数、长径比和外形对药粒应力的影响。结果表明，药粒被压缩后发生回弹，与落锤接触面的应力从圆心到边界逐渐增加，药粒中部发生膨胀；受孔处应力集中的影响，孔数的增加改变了端面应力分布连续性，和单孔药相比，七孔药的受力时间和最大压缩位移分别增长了3.39%和3.76%，十九孔药的受力时间和最大压缩位移分别增长了10.17%和15.05%；当孔数不变，长径比从1：1增加到2：1时，应力峰值减小而压缩位移峰值增大；花边形药粒比圆柱形药粒更易在花边凹陷处出现应力集中。对发射药应力响应过程及影响因素的研究为发射药力学性能研究提供了基础数据。“,”In order to investigate the mechanical response process of porous propellant under impact loading and the effect of geometric parameter changes on the mechanical properties of the particles， ANSYS/LS‑DYNA was used to establish the numerical models of seven‑hole and nineteen‑hole propellants to simulate the force of the particles under impact loading. Then， the models of single‑hole propellant， seven‑hole and nineteen‑hole propellants with aspect ratios of 1∶1 and 2∶1， and lace‑shaped seven‑hole and nineteen‑hole propellants were established to study the influence of the number of holes， aspect ratios and shape on propellant stress. The results show that the particles rebound after being compressed， the stress on the surface in contact with the drop hammer increased gradually from the center to the boundary， and the middle of the particles expanded. The increase of the number of holes will change the continuity of the stress distribution on the end surface due to the stress concentration at the hole. Compared with the single‑hole propellant， the duration under stress and the maximum compressive displacement of the seven‑hole propellant are increased by 3.39% and 3.76%， respectively， whereas the duration under stress and the maximum compressive displacement of the nineteen‑hole propellant are increased by 10.17% and 15.05%， respectively. When the number of holes remains constant and the aspect ratio increases from 1∶1 to 2∶1， the peak stress decreases and the peak compressive displacement increases. The lace‑shaped particles were more prone to cause stress concentration in the concave of lace than the cylindrical ones. The study of the stress response process of the propellant and its influencing factors provides fundamental data to study the mechanical properties of the propellant.