Numerical Study of Mechanical Properties of Composite Solid Propellant with Initial Defects

Abstract

In order to study the effect of initial interface defects and initial void defects on the macro tensile mechanical properties of composite solid propellant, based on the Python script, the particle filling model of composite solid propellant with meso pores and interface defects was established in ABAQUS. Firstly, zero thickness cohesive elements were embedded at the adjacent elements of the matrix and the particle/matrix interface, and the traction separate law was used to simulate the fracture failure of composite solid propellant. Then, the influence of different shapes, porosity and interface defect ratio on the elastic modulus and tensile strength of composite solid propellant was studied. Accordingly, the relationship between the initial damage of the composite solid propellant and the porosity and interface defects was established. Morever, the initial damage surface of the composite solid propellant was depicted. Results showed that the initial damage of polygon filling model is larger than that of circular particle filling model under the same initial defect condition; The elastic modulus of composite solid propellant decreases linearly with the increase of porosity and interface defect ratio; The tensile strength of composite solid propellant decreases linearly with the increase of interface defect ratio, and decreases logarithmically with the increase of porosity.