Three-dimensional Impact Response Of Solid Propellant Based On A Viscoelastic Model

Abstract

The three-dimensional dynamic response of a solid propellant rocket motor subjected to projectile or fragment impact is modelled on a viscoelastic basis with complex modulus. The propellant is in a form of thick hollow cylinder housed in an elastic metal casing simply supported at both ends. The three-dimensional consistent higher-order theory is employed in that 3-D boundary conditions and interface continuity of transverse stresses are emphasized on the exterior and interior. Dynamic displacement fields are assumed as a combination of Legendre polynomials and double Fourier series in cylindrical coordinates. Upon impact by a high velocity projectile or fragment, hot spots are found theoretically for the highest pressure and temperature via the three-dimensional stresses along with the traditional equation of state. Predicted ignition, growth zone and detonation compared well reasonably with existing literature.