| Type of Document |
Master's Thesis |
| Author |
Mandal, Anirban
|
| Author's Email Address |
amanda2@lsu.edu,anirban.ind@gmail.com |
| URN |
etd-08112010-163505 |
| Title |
Computational Examination of Compaction Wave-Boundary Interaction in Granular Explosive |
| Degree |
Master of Science in Mechanical Engineering (M.S.M.E.) |
| Department |
Mechanical Engineering |
| Advisory Committee |
| Advisor Name |
Title |
| Gonthier, Keith A. |
Committee Chair |
| Guo, Shengmin |
Committee Member |
| Nikitopoulos, Dimitris E. |
Committee Member |
| Pang, Su-Seng |
Committee Member |
|
| Keywords |
- Granular HMX
- Accidental initiation
- Dynamic compaction
- Granular energetic solid
- Oblique reflection
- Normal reflection
- Rate-dependent compaction
- Inelastic compaction
- Compression
|
| Date of Defense |
2010-08-06 |
| Availability |
unrestricted |
Abstract
Interactions between initially planar, piston supported compaction waves in heterogeneous energetic solids and macro-scale rigid boundaries were computationally examined for a wide range of piston impact speeds (20 ≤ Up ≤ 500 m/s) and initial solid volume fractions of the material (0.73 ≤ ϕ0 ≤ 0.90). The response of the material was described by a continuum theory that accounts for both elastic and inelastic compaction in a thermodynamically consistent manner. Initial conditions were imposed by interpolating the spatial structure of one-dimensional steady compaction waves onto two-dimensional domains considered in this study. For a planar wedge boundary, the peak solid pressure (Ps), dissipative heating rate (ėc) and bulk temperature rise (ΔT) at the boundary increased when wedge angle θ was increased from 0º to a critical value (60º ≤ θc ≤ 65º) as the flow transitioned to a single Mach reflection (SMR) from a von Neumann reflection (vNR); these quantities decreased when θ was further increased due to flow transition to a regular reflection (RR) from a SMR for ϕ0 = 0.85 and Up = 500 m/s. Locations of the peak Ps, ėc and ΔT were predicted to be removed from the wedge tip for a vNR and a SMR, but near the wedge tip for a RR. Qualitatively similar predictions were obtained for 0.73 ≤ ϕ0 ≤ 0.90 and Up ≥ 150 m/s. For a semi-circular boundary, the initial RR configuration transitioned to a SMR for all cases. For 0.73 ≤ ϕ0 ≤ 0.90 and Up ≥ 150 m/s, peak values of Ps, ėc and ΔT were predicted at a location removed from the stagnation point. For both wedge and semi-circular boundaries, dissipative heating at the boundary was dominated by rate-dependent compaction. To aid in the development of a bulk-scale combustion sub-model, bulk-scale predictions were compared to locally averaged meso-scale predictions. Bulk-scale and averaged meso-scale predictions showed good agreement, provided that the averaging area size was suitably selected.
|
| Files |
| Filename |
Size |
Approximate Download Time
(Hours:Minutes:Seconds)
|
| 28.8 Modem |
56K Modem |
ISDN (64 Kb) |
ISDN (128 Kb) |
Higher-speed Access |
| |
Mandal_thesis.pdf |
13.61 Mb |
01:03:00 |
00:32:24 |
00:28:21 |
00:14:10 |
00:01:12 |
|
