基于细观结构的HTPB固体推进剂含损伤粘弹性本构模型研究

Viscoelastic constitutive model of HTPB solid propellant with damage based on mesostructure

基于对HTPB推进剂的拉伸试验,结合推进剂的细观结构对拉伸曲线进行分段和拟合;建立了推进剂四阶段损伤模型,并将推进剂的力学性能构成分为基体-颗粒界面和基体两部分,提出了推进剂杨氏模量的叠加模型;在试验和拟合结果的基础上,分别建立基体-颗粒界面和基体的损伤方程,较为准确地描述了推进剂拉伸损伤过程,并将其引入杨氏模量的叠加模型;结合现有积分性本构模型,给出了基于细观结构的HTPB推进剂含损伤粘弹性本构模型,并通过不同应变率条件下的拉伸试验进行了验证,结果显示模型预测结果较好。

Based on the tensile test of the HTPB propellant and the meso-structure of the propellant,the tensile curve is segmented and fitted to establish a four-stage damage model for the propellant.The mechanical properties of the propellant are divided into two parts:the matrix-particle interface and the matrix.A superposition model of Young’s modulus of propellant is proposed.On the basis of the test and fitting results,the damage equation of the matrix-particle interface and the matrix is established.It can describe the propellant tensile damage process more accurately.And introduce it into the superposition model of Young’s modulus.Combined with the existing integral constitutive model,a damage-containing viscoelastic constitutive model of HTPB propellant based on the meso-structure is given.It is verified by tensile tests under different strain rates,and the results show that the model prediction results are better.