A Calculation Analysis For Structural Integrity Of Solid Propellant Motor Under High Overload

The two-dimensional non-linear viscoelasticity analysis of stress strain and displacement fields for solid motor grains under light overload (acceleration) is carried out using finite element method in this paper .The deformation results of propellant grains and transverse and axial overload are abstained. On base of viscoelastic theory and using inversion of the Laplace transform and numerical calculation method. A formation and a numerical solution for viscoelastic poissonratio v(t) from stress tension modulus E(t) and bulk relaxation modulus K(t). The exact and approximate inversion relationships between volume relaxation modulus K(t) and volume creep compliance B{t) are summarized.Based on theProny method, a fitting method of solid propellant relaxation modulus master curve and parameter of W.L.F. equation by using test data is put forward. A uniform fitting model is set up. The method and process including failure tree analysis analysis of data curve reexamination and testing. Based on the theory of viscoelasticity and dynamics, the structural integrality analysis of solid rocket motor in the Finite Element Method (ANASYS 6.1) is presented in this paper. The grain FEM model is used to figure out the stress and strain under compound load case, such as inertial force in radius direction and metrical force on axis direction, to estimate if the intensity and deformation can meet the demand to find out the reasons and mechanism of the failure. It is available for reference to the structure design of high-acceleration solid rocket motor grains.