PRELIMINARY INVESTIGATIONS ON THE MECHANICAL DESIGN OF HARDENED FOAM RADOMES
Abstract
All static and dynamic tests developed at Lincoln Laboratory which relate to the evaluation of polyurethane foam systems for the construction of hardened foam radomes are presented. Hydrostatic buckling tests were made on spherical ap specimens 27.5 in. in diameter, 4.27 in. high, and 11/32, 11/16 and 1 3/8 in. thick fabricated to different density levels. The critical pressure required to buckle the cap specimens is expressed as a function of the foam density, and thickness to radius. The response of scale model foam radomes, 27.5 in. in diameter and 19.5 in. high, to blast overpressure loads was investigated by subjecting models to shock overpressures of increasing intensity, generated by primacord de onations within a 6-ft diameter shock tube, until failure resulted. Three different foam density levels, 10, 13 and 16/cu ft, were investigated for a shell thickness of 11/16 in. and 3 different shell thicknesses, 11/32, 11/16 and 1 3/8 in., for a foam density level of 10/cu ft. Sufficient evidence was compiled to demonstrate that polyurethane foam materials can be used to construct a hardened radome capable of withstaning 5 psi free-air blast overpressures. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 03, 1962
- Accession Number
- AD0275713
Entities
People
- R.a. Muldoon
Organizations
- Massachusetts Institute of Technology