Improved Barriers to Turbine Engine Fragments: Interim Report II
Abstract
Because fragments from in-flight engine failures can damage critical aircraft components and produce catastrophic consequences, the Federal Aviation Administration is sponsoring research to mitigate the effects of uncontained engine bursts. SRI International is evaluating the ballistic effectiveness of fabric structures made from advanced polymers and developing a computational ability to design fragment barriers. In this reporting period, SRI solved several numerical problems associated with modeling the crimped geometry and interaction of woven yarns. When an orthotropic model is invoked and direction-dependent yarn properties specified, the yarn, as it is loaded, exhibits no appreciable stiffness until it straightens. The model behaved properly in simple simulations of single yarn response to axial and transverse loads. Laboratory and field site tests were performed to provide data for developing and validating the computational model. The ballistic response of fabrics to fragment impact was evaluated; the phenomenology of fabric deformation and failure was elucidated in quasi-static penetration tests; and the tensile properties of yarns and fibers were measured. Three high-strength polymer materials were examined: PBO (Zylon), aramid (Kevlar), and polyethylene (Spectra). Future work will include verification of the microstructural fabric model by implementing it into the DYNA3D code, simulating the static and dynamic penetration tests, and comparing the results. The material properties most important in resisting penetration will be identified and the effects of boundary conditions investigated. SRI will also perform fragment impact tests to generate data on boundary condition effects, measure yarn-on-yarn friction, and participate in full-scale fragment barrier tests at the Navy Air Warfare Center.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1999
- Accession Number
- ADA368841
Entities
People
- David C. Erlich
- Donald A. Shockey
- Jeffrey W. Simons
Organizations
- SRI International