A nonlinear viscoelastic constitutive model of solid propellant
A composite solid propellant is a lightly cross-linked, long-chain polymer filled with solid particles. Such a material exhibits highly nonlinear viscoelastic response due to the damage process, debonding, vacuole formation and cracking under various loading damage. The nonlinearities of solid propellants are mainly due to the Mullin's effect and dewetting. Here the authors propose a nonlinear constitutive model of composite solid propellant by using a viscoelastic dewetting criterion for predicting critical stress at which the dewetting occurs. The softening of the solid propellant due to damage is treated by the modulus decrease, and the stress-strain relation is formulated by using the second Piola-Kirchhoff stress and Green strain tensors. Experimental results show that the model predicts the large range of propellant behaviour with a resonable accuracy.
scientific article; zbMATH DE number 1341442