摘要
填充颗粒的形貌对复合固体推进剂细观力学性能具有重要影响。考虑相界面和颗粒形貌的影响,在细观层次上建立了代表性体积单元(RVE)计算模型,通过引入内聚力模型(CZM),研究了混合颗粒形状、混合颗粒粒度级配以及不规则填充颗粒等细观颗粒形貌因素对复合固体推进剂力学性能的影响。结果表明:当模型填充颗粒均为粒径150μm的小颗粒时,填充形貌对其力学性能影响很小,而填充颗粒为粒径290~420μm的大颗粒时,颗粒越圆润,其界面处更容易发生“脱湿”损伤,导致其力学性能明显下降;在具有相同大颗粒圆形填充物时,小颗粒形貌对初始模量影响较大,若小颗粒长径比由1增大到2,其初始弹性模量减小,而最大抗拉强度变化较小;而在具有相同椭圆形大颗粒填充物时,具有圆形小颗粒填充物的最大抗拉强度更大;多边形填充颗粒模型与圆形填充颗粒模型界面失效模式有所不同,前者力学性能明显高于后者。因此,当细观填充颗粒形貌差异较大时,推进剂力学性能较好。
In order to study the influence of filling particle morphology on the microscopic mechanical properties of composite solid propellants,a representative volume elements(RVE)computational model was established at the microscopic level by considering the phase interface and particle morphology.The influence of different microscopic particle morphologies on the macroscopic mechanical properties of composite solid propellants,including different mixing particle shapes,mixing particles with gradation and irregularly filled particles,was investigated through the introduction of a cohesive zone model(CZM).The results show that:when the model filler particles are all small particles of 150μm diameter,the filler morphology has little effect on the mechanical properties,while the filler particles are large particles with a grain size of 290μm to 420μm,the more rounded the particles are,the more likely to occur“dehumidification”damage at the interface,resulting in a significant decrease in the mechanical properties;in the case of circular filler with the same large particles,the morphology of small particles has a greater impact on the initial modulus,and if the aspect ratio of small particles increases from 1 to 2,the initial elastic modulus decreases,while the maximum tensile strength changes are smaller;in the case of the same ellipsoidal filler with large particles,the maximum tensile strength of the filler with small round particles is larger;the interfacial failure modes are different in the polygonal filled particles model,the circular filled particles model,mechanical properties of the polygonal filling model are significantly higher than that of the circular filled particles.Therefore,it can be concluded that the mechanical properties of the propellant are better when there is a large difference in the morphology of the finer filler particles.
作者
张文宇
魏乐
庞维强
刘殊远
白帅帅
胡松启
ZHANG Wenyu;WEI Le;PANG Weiqiang;LIU Shuyuan;BAI Shuaishuai;HU Songqi(National Key Laboratory of Solid Rocket Propulsion,Northwestern Polytechnical University,Xi’an 710072,China;Xi’an Institute of Modern Chemistry,Xi’an 710065,China)
出处
《固体火箭技术》
CSCD
北大核心
2024年第6期840-850,共11页
Journal of Solid Rocket Technology
关键词
颗粒形貌
复合固体推进剂
细观结构
界面脱湿
力学性能
particle morphology
composite solid propellant
mesostructure
interface debonding
mechanical property
作者简介
张文宇,男,硕士生,研究方向固体推进剂细观建模;通讯作者:刘殊远,男,博士/副教授,研究方向为固体推进剂力学性能及燃烧仿真。
