Finite-Difference Code Analyses of Earth Penetrator Dynamics in Rock Media.
Abstract
Numerical analyses of penetration dynamics have been performed in support of a program to develop technology for earth penetrating weapons. The emphasis in this program has been to apply calculational techniques to the analysis of projectile penetrations in rock media. Observations from penetrator firings into rock show that there is a region of highly comminuted rock surrounding the penetrator and the penetrator cavity. Since the penetration dynamics are sensitive to the physical properties of the material next to the penetrator, it becomes important to account for the breakup and fracture of the rock in the analysis techniques. Accordingly, material models were developed that included fracture and a post-fracture process which degrades the physical properties to that of a comminuted rock. The penetration analyses were performed with WAVE-L, a two-dimensional Lagrangian finite-difference code. A decoupled calculational method is employed, wherein the penetrator is treated as a rigid body to compute the penetration dynamics. Using the force loadings on the penetrator obtained from this solution, subsequent analysis may be made of the interior response of the penetrator. To test and demonstrate the code, pre-event calculations of a specific rock penetration field test were made. The field experiment consisted of the vertical firing of a 400 pound steel penetrator into a massive welded tuff site at a velocity of 1500 ft/sec. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1976
- Accession Number
- ADA049158
Entities
People
- C. C. Fulton
- K. N. Kreyenhagen
- M. H. Wagner