• Journal of the Korean Society of Propulsion Engineers
• /
• v.24 no.2
• /
• pp.43-51
• /
• 2020

After the accelerated aging, the bulkhead initiator using high explosives was carried out to verify aging characteristics. The Thru-Bulkhead Initiator operates by transmitting shock-wave generated from micro-initiator to the acceptor and the ignition explosives through the bulkhead. In order to evaluate the life-time of the product, the accelerated aging condition was set according to the life-time, and the ignition performance of the sample was measured every 10 cycles by measuring the delay time and the maximum pressure through the 10cc closed bomb test. In addition, variance analysis was used to determine aging.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2017.05a
• /
• pp.440-444
• /
• 2017

Two-dimensional hydrodynamic analysis was performed to analyze the attenuating characteristics of shock waves generated by the detonation of the bulkhead initiator. Through the interlocking analysis between HNS and HMX stacking initiator and STS bulkhead, we have precisely simulated detonation growth and pressure wave attenuation phenomena. The free surface velocity at the surface of the bulkhead was measured for quantitative comparison with the test data by VISAR. As a result, it was confirmed that the pressure attenuating pattern of the shock wave exponentially decreased according to the bulkhead thickness. The observed inflection point at the particle velocity measured over time is due to the subsequent propagation of the shock wave due to the rapid spallation of the interface between the detonator and the bulkhead.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.21 no.4
• /
• pp.36-43
• /
• 2017

We studied attenuation characteristics of shock waves induced by a donor charge and the sensitivity of an acceptor for optimal design of a TBI (Through-bulkhead initiator). The attenuation behavior of shock waves was studied by measuring free surface velocity using a VISAR (Velocity Interferometer System for Any Reflector), and the sensitivity of the acceptor explosives was analyzed via SSGT (Small Scale Gap Test). It was found that the acceptor sensitivity obtained by the SSGT may be inappropriate for the design of the small-scale explosive devices such as TBI due to the different shock duration time.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.20 no.5
• /
• pp.19-30
• /
• 2016

We presented a hydrodynamic modeling necessary to accurately reproduce shock-induced detonation of pyrotechnic initiator. The methodology for such numerical prediction of shock propagation is quite straight forward if the models are properly implemented and solved in a well-formulated shock physics code. A series of SSGT(Small Scale Gap Test) and detailed hydrodynamic simulation are conducted to quantify the shock sensitivity of an acceptor that contains 97.5% RDX. A TBI(Through Bulkhead Initiator) system, consisting of a train configuration of Donor(HNS+HMX) - Bulkhead(STS) - Acceptor(RDX), were investigated to further validate the interaction between energetic and non-reactive materials for predicting the detonating response for successful operation of such small pyro device.