Application development for explosive process simulation and choice of protection
Now full-fledged solution of detonation processes and interaction of explosion with structures to carry out in standard FEA complexes is not possible. Though solver LS-DYNA successfully solves such problems. The most part of possibility LS-DYNA solver is not realized in interface. And use package LS-DYNA to solve such problems much in a complicated way. Solver LS-DYNA, allows to solve full-fledged both ordinary durability, and the coupled-field, mechanics and thermo-gas-mechanics problems, it is especially good for high-velocity shock processes with destructions.
By studied works in the field of explosive processes calculations, was create the complex solution, which allow to ANSYS\LS-DYNA successfully solve the problems of simulation any standard explosives. This is reached to account of use ANSYS as pre-postprocessor shells, LS-DYNA as solver. Illustrated program is autonomous, oriented on ordinary engineer, who not having ANSYS skills and more so LS-DYNA. This module started autonomous, is necessary only to enter the input data about designed shield and choose the type of explosive. All be rest module executes by itself, without interference of engineer.
Complex created by the public data in research Internet library http://stinet.dtic.mil/ [1-20].
It has the following choice of solution variants:
1. Solve 35 types of explosives:
BTF, Comp A-3, Comp B (Grade A), Comp C-4, Cyclotol 77/23, DIPAM, EL-506A, EL-506C, Explosive D, FEFO, H-6, HMX, HNS r=1000, HNS r=1400,
HNS r=1650, LX-01, LX-04-1, LX-07, LX-09-1,
LX-10-1, LX-11, LX-14-0, LX-17-0, NM, Octol-78/22, PBX-9010, PBX-9011,
PBX-9404-3, PBX-9407, PBX-9501, PBX-9502, Pentolite50/50, PETN, TETRYL, TNT;
2. Varies the count of layers of shield from 1 to 3;
3. Varies the shield layers materials: Steel, Kevlar, Å-glass, S-glass, metal foams;
4. Varies the count of layers in cross-armed composite materials;
5. Allowed the possibility to glue of layers of shield;
6. Varies the depth of grounding explosive in to soil;
7. Varies the distance from first sheet of shield to explosive;
8. Varies the mass of explosive;
9. Varies the steels characteristics, i.e. it possible to simulate any isotropic material with nonlinear characteristics;
10. Automatically defines the ANSYS location, in case of its absences a solution is blocked;
11. Possibility to store results of solution for the further postprocessing in ANSYS;
12. Automatic generation of results report in format Microsoft Word and animation files of velocities, stresses and plastic strains. Writing the report automatically.
Simulation based on 1-point ALE multi-material solid elements for air, soil and explosive. Hughes-Liu shell elements for shield. Solution algorithm for multi-material mixing process *ALE_MULTI-MATERIAL_GROUP_SET and *INITIAL_VOLUME_FRACTION with Arbitrary Lagrangian Eulerian advection method Van Leer+HIS + Equilibrium smoothing. The contacts pair are formed between of shield layers.
The mathematical methods is marketed on the base of license complex LS-DYNA, theoretical support of users LS-DYNA [1-20], and powerful cluster computing system.
In picture was shown an example simulation of explosive of mine by weight 10 kg Ñ-4 under by layered armor, consisting of aluminum foam, recoated by fiberglass of type S-glass.
The scheme of typical location an explosive to shield. The section.
Distribution of detonation products velocities and soil and armor deformation.
Process of solution monitoring
The reactions, stresses and deformation on armor sheets during blast.
The theoretical bases:
1. LLNL Explosives Handbook. Properties of Chemical Explosives and Explosive Simulants, Personal Authors: Dobratz, B. M.; Crawford, P. C. ADA272275 1985
2. J.Wang SIMULATION OF LANDMINE EXPLOSION USTNG LS-DYNA3D SOFTWARE: Benchmark Work of Simulation of Explosion in Soil and Air DSTO-TR-1168
3. Jing Ping Lu and David L. Kennedy Modelling of PBX-115 Using Kinetic CHEETAH and the DYNA Codes DSTO-TR-1496
4. Daniel Hilding. Simulation of detonation chamber test case. Engineering Reseach Nordic AB. Garnisonen I4, Byggnad 5 SE-582 10 Linkoping 2001.
5. G. McIntosh The Johnson-Holmquist Ceramic Model as used in LS-DYNA2D. Reseach and development branc department of national defense Canada. DREW-TM-9822. 1998.
6. LS-DYNA KEYWORD USER'S MANUAL VOLUME I LIVERMORE SOFTWARE TECHNOLOGY CORPORATION March 2001
7. LS-DYNA KEYWORD USER'S MANUAL VOLUME II LIVERMORE SOFTWARE TECHNOLOGY CORPORATION March 2001
8. O. Hallquist LS-DYNA THEORETICAL MANUAL LIVERMORE SOFTWARE TECHNOLOGY CORPORATION May 1998
9. L.L.Clements, R.L.Moore. Composite properties for E-glass in a room temperature curable epoxy matrix. Lawrence Livermore laboratory, 1977.
10. L.L.Clements, R.L.Moore. Composite properties for S-2-glass in a room temperature curable epoxy matrix. Lawrence Livermore laboratory, 1978.
11. L.L.Clements Problem intesting aramid/epoxy composites. Lawrence Livermore laboratory, 1977.
13. J.H. Underwood, A.P.Parker, P.J.Cote, S.Sopok Compressive thermal yielding leading to hydrogen cracking in fired cannon. Technical report ARCCB-TR-98006
14. R.D. Streit Comparation of linear-elastic-plastic, elastic-plastic, and fully plastic failure models in the assessment of piping integrity. Lawrence Livermore National Laboratory, Livermore, California 94550. UCRL- 84182
15. N.F. Knight, Jr., N.Jaunky, R.E.Lawson, D.R.Ambur. Comparation of two modeling approaches for thin-plate penetration simulation. Verdan-MRJ, Yorktown, VA, USA.
16. W.B. Kratzig, Y.S. Petryna. Assessment of structural damage and failure. Applied Mechanics 71 (2001) 1-15 Springer-Verlag 2001.
17. Jing Ping Lu and David L. Kennedy Modelling of PBX-115 Using Kinetic CHEETAH and the DYNA Codes DSTO-TR-1496 Australian Government Department of Defence Defence Science and Technology Organisation DSTO Systems Sciences Laboratory PO Box 1500 Edinburgh South Australia 5111 Australia Commonwealth of Australia 2003 AR-012-899
18. Heiner MUllerschon, Ulrich Franz, Thomas Miinz, Nielen Stander CAD-FEM GmbH, Grafing/ Munich, Germany Livermore Software Technology Corporation, Livermore, C A The identification of rate-dependent material properties in foams using LS-OPT.
19. Albert L. Nichols III. Nonequilibrium Detonation of Composite Explosives UCRL-JC-126866 PREPRINT19971997 Topical Conference on Shock Compression of Condensed Matter of the American Physical Society Amherst, MA July 27 - August 1, 1997
20. Gerald L. WTT A diffusion-reaction model of a composite high explosive. Jourmal of chemical physics. December 24, 1986.UCRL- 96183 PREPRINT