Accession Number : AD0283361

Title :   PHOTOELASTIC STUDY OF THE XM50 GRAIN CONFIGURATION

Corporate Author : EMERSON ELECTRIC CO ST LOUIS MO

Report Date : 28 FEB 1962

Pagination or Media Count : 1

Abstract : Photoelastic tests were conducted to determine the stress concentration factor and define the stress field pattern of the XM50 grain assembly. The small fillet between the propellant web and strut intensifies the stresses induced by the pressure differential. Further redesigns should consider an appreciable increase in this radius to lessen the stress raising effect. The cross section at time zero has the smallest fillet radius and the largest stress concentration factor. The configuration at 1.5 seconds after ignition has a generous radius at the fillet and a small stress concentration factor. The effects of fillet radius and web thickness on the stress concentration factor are shown. The effects of the strut height is also pertinent to the stress concentration factor. As the grain approaches the shape of a cylinder the stress concentration factor decreases regardless of the fillet radius. This is demonstrated by the forward and aft cross sections, both with the same fillet radius, but different strut heights. The aft section with the shorter struts has a lower stress concentration factor. The effects of the struts are also shown in the stress field pattern. (Author)

Descriptors :   *LOAD DISTRIBUTION, *PROPELLANT GRAINS, *SOLID ROCKET PROPELLANTS, *STRESSES, CONFIGURATION, TESTS

Distribution Statement : APPROVED FOR PUBLIC RELEASE