Viscoelastic analysis method for rocket motors containing cracks

Abstract

The basic definitions for viscoelastic stress intensity factors are set forth with associated computations for determining them in laboratory specimens. Laboratory tests have been conducted to characterize propellants fracturewise. and the most suitable test found was the long strip subjected to a constant force loading. The influence of dewetting on the fracture characterization appears to be significant, but the matter has not yet been fully resolved. An approximate method for performing viscoelastic fracture analyses has been presented which incorporates the fore-mentioned fracture characterization. It requires minimum computer usage and should yield good results. (Author)