Nonlinear Viscoelastic Analysis of Double Base Propellant

Abstract

This study presents the characterization of the nonlinearly viscoelastic behavior of double base propellant (DBP) using Schapery-type constitutive model in the different conditions of temperature, strain level and strain rate. A recursive-iterative numerical algorithm is generated for the Schapery-type nonlinearly viscoelastic constitutive and implemented in a displacement-based finite element (FE) code for ABAQUS user material subroutines. Then, the model parameters are obtained by analyzing the response of creep-recovery tests and constant rate tensile tests at different temperatures, strain levels and strain rates. And find a linear relationship between temperatures and the effective stresses which determine the limit of linear viscoelactic. The FE model with the calibrated time-dependent and nonlinear material parameters is used to simulate the creep-recovery tests and the constant rate tensile tests, and reasonable predictions are shown.