摘要
固体推进剂粘弹性泊松比严重影响着药柱结构完整性的分析精度。针对点火增压过程药柱的受力特点,基于数字图像相关(Digital Image Correlation,DIC)方法,设计了可测试推进剂粘弹性泊松比的单向定速拉伸试验,研究了温度和拉伸速率对推进剂粘弹性泊松比的影响规律,利用粘弹性材料参数的应变率温度等效原理,建立了参考温度下推进剂粘弹性泊松比的应变率主曲线。研究表明,推进剂的粘弹性泊松比随温度和拉伸速率的增大而增大,当拉伸速率达到 500mm/min时,推进剂泊松比逐渐趋近于某一常值。考虑到发动机点火增压过程,药柱的加载速率一般在0.5s-1以上,应变率较大,因此可以将推进剂的泊松比取为一常数,但必须考虑发动机的工作温度,选取合适的泊松比。相关方法和结论可为固体发动机结构完整性分析和贮存寿命预估提供参考。
The viscoelastic Poisson’s ratio of solid propellant seriously affects the analytical precision of the structural integrity of the column.Considering the force characteristics of the ignition pressurization process,based on the digital image correlation (DIC) method,a one way fixed speed tensile test for testing the viscoelastic Poisson’s ratio of the propellant has been designed.The effects of temperature and tensile rates on the viscoelastic Poisson’s ratio of solid propellants have been studied.The strain rate- temperature equivalent principle for viscoelastic material parameters has been used to establish the viscoelastic Poisson’s ratio strain rate main curve of the propellant under a certain reference temperature.The research shows that the viscoelastic Poisson’s ratio of the propellants increases with the increase of temperature and tensilerate.When the tensile rate reaches 500mm/min,thepropellant Poisson’s ratio gradually approaches a constant value.Considering the motor ignition and pressurization process,the loading rate of the propellants charge is generally above 0.5 s-1,and the strain rate is large.The Poisson’s ratio of the propellants can be taken as a constant,but it must be selected according to the actual operating temperature of the motor.Relevant methods and conclusions can provide a reference for structural analysis and storage life prediction of solid motors.
作者
吕轩
申志彬
崔辉如
LYU Xuan;SHEN Zhibin;CUI Huiru(College of Aerospace Science and Engineering,National University of Defense Technology,Changsha 410073,China)
出处
《固体火箭技术》
EI
CAS
CSCD
北大核心
2019年第3期322-326,共5页
Journal of Solid Rocket Technology
基金
国家自然科学基金资助项目(11872372)
国防科技大学科研计划资助项目(ZK17-02-06)
关键词
固体推进剂
粘弹性泊松比
DIC
方法
单向定速拉伸试验
应变率温度等效原理
应变率主曲线
solid propellants
viscoelastic Poisson’s ratio
DIC method
one way fixed speed tensile test
strain rate temperature equivalent principle
strain rate main curve
