Fig. 1. Operating sequence on flyer impact initiation of an exploding foil initiator
Fig. 2. Calculation results for flyer velocity at 2.0 and 2.5 km/s on HNS detonator
Fig. 3. Impact pressure profile
Fig. 5. Schematic of pyrotechinc bulkhead initiator and timed images of calculated pressure contour at t = 0 – 3.5 μs with pressure range 0 - 10 GPa
Fig. 4. Free surface velocity profiles
Fig. 6. Time trace of shock attenuating pressure along STS bulkhead (dot : experimental data, dotted line : calculation data, red line : fitted data)
Fig. 7. Test specimen (upper) and computational domain (lower) for closed chamber test
Fig. 8. Pressure histories for Go/No-go cases
Fig. 9. Raw and filtered pressure profiles
Fig. 10. Power spectral densities of closed chamber test data
Fig. 11. Timed images of pressure at (a) 3.8 mm, and (b) 4.0 mm bulkhead of explosive train
Fig. 12. Shock pressure trajectory in Detonator – Bulkhead - Acceptor of pyrotechnic initiator
Fig. 13. Reaction and regression rates of BPN based on the Arrhenius temperature dependence
Fig. 14. Shown schlieren (top) and pressure (bottom) evolution in time for entire pyrotechnics-chamber assembly that shows a detonator (HNS+HMX), bulkhead (STS), acceptor (RDX), and gas-generating propellant (BPN)
Fig. 15. Shape comparison of pyrotechnic device between calculation and experiment
Fig. 16. Comparison of pressure signal inside the chamber between calculation and experiment
Table 1. Modeling constants for HNS, HMX, RDX(pure) and CH-6(97.5% RDX)
Table 2. Material properties for STS[12,13].
Table 3. CBT Experimental Result
Table 4. Nominal Arrhenius law and JWL EOS parameters for BPN
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