Personal tools

Session 18

Simulation of shock absorbers behavior during a 9m drop test
TN International designs, manufactures and licenses packages for the transportation of radioactive materials. To justify the leaktightness and then insure the safety of a package during an accident event, a 9m drop test onto an unyielding target has to be considered. The corresponding kinetic energy is generally absorbed by shock absorbers filled with wooden blocks. In order to improve the numerical simulation of those shock absorbers, a benchmark has been performed using a specific drop test exhibiting an important crushing. This study has led to the improvement of the wood material law, including shear damage effect. The welds failure was also implemented to improve results. This paper will show the main results of this study.
Computational simulations of aluminum foam projectile behavior
The results of experimental tests and computer simulations of open-cell aluminum foam behavior under high deformation rates are presented. Experimental Taylor impact tests showed, that the open-cell foam projectile deforms already during its acceleration in the Taylor barrel. This behavior was investigated further by use of computer simulations with the LS-DYNA. The simulations confirmed very high sensitivity of open-cell foam projectile to the acceleration.
Numerical simulation of spiral-strand cables subjected to high velocity fragment impact
This paper presents the results of a numerical study carried out to evaluate the response of high-strength steel spiral-strand cables, when subjected to high velocity fragment impact. A detailed numerical model of a 60 mm diameter spiral-strand cable subjected to impact from a 20 mm fragment simulating projectile has been developed for analysis in LS-DYNA. Detailed consideration was given to the complex geometry of the cable, wire-to-wire contact and friction, cable-end boundary conditions and appropriate material modelling. Fragment velocities between 200 and 1400 m/s were modelled to assess the penetration and perforation resistance of the cable and to study the magnitude of localised cross-sectional cable damage. The numerical results were validated against initial laboratory tests. In both the tests and numerical simulations none of the cables were perforated by the fragments and good agreement was seen in the damage area, the fragment penetration depth and the wire splay phenomenon.
LS-DYNA application to develop a package for air transportation of fissile materials
Object of computer study is a package for FM storage and transportation based on a container AT-400R [1]. Shock and fire resistant container AT-400R was designed at Sandia National Laboratories (USA) and was tested by US and Russian specialists in compliance with the IAEA regulations [2], including cases of flooding, falling of a slab with mass 500 kg from the height of 9 m, container dropping from the height of 1 m onto the pin 150 mm in diameter. In the frames of the ISTC projects # 1216 and 1449, performed computation proved that the IAEA regulations to safe transportation of FM are met. Besides, computation determined limited loading, when 500 kg slab falls from the height of 50 m and freefall of the container from the height of 50 m. When this limited value of loading is outranged, inner containment vessel looses tightness. The objective of this work is to develop a package, based on this container, for FM air transportation, which will provide FM pressure-sealing in conditions that are regulated by up- to-date IAEA requirements – package collision with a target at a velocity 90 m/s.