Dynamic fracture of explosive bolt

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Date

2018

Author

Gökçe, Batuhan

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In this study, dynamic fracture of the pressure type explosive bolt is established with different geometry of the piston, which is used to break the body, to enhance the reliability of the system. Before the fracture analysis of the explosive bolts, pyrotechnic combustion analysis is studied and 0-D ballistic solver is developed to simulate the performance of the initiator into the pyrotechnic, namely pressure type, explosive bolt. By using the developed model, the pressure and temperature in the expansion chamber, the position and velocity of the piston can be predicted. After prediction of these parameters, the pressure expansion is validated with closed bomb experiments. Then, three different shape piston models are developed to study on clean separation without fragmenting parts with minimum dissipated of energy during the separation of the system to get higher reliability. The varied separation behavior of these pyrotechnic explosive bolt models are analyzed and compared in LS-DYNA.

Subject Keywords

Bolts and nuts., Pyrotechnics.

URI

http://etd.lib.metu.edu.tr/upload/12622243/index.pdf
https://hdl.handle.net/11511/27353

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

B. Gökçe, “Dynamic fracture of explosive bolt,” M.S. - Master of Science, Middle East Technical University, 2018.