VISCOELASTIC ANALYSIS OF STRESSES AND STRAINS IN SOLID PROPELLANT GRAINS UNDER PRESSURE LOADINGS
This paper is devoted to the viscoelastic analysis of stresses and strains resulting from pressure loadings. Some engineering methods for solving this classical problem have been developed. For example, formulas were derived on the assumption that propellants are incompressible or cases of the motor are undeformed, and some other formulas are derived without these assumptions, but Schapery's approximate inversions were used to obtain viscoelastic solutions. In this paper, a new method is developed without using above assumptions and approximate inversions. Therefore, the solutions of stresses and strains are more accurate than the above.The solutions of these two planar problems are the results under the suddenly-applied pressure and gradually-applied pressure.