Swietek Bogumila, Skotak Maciej, Chandra Namas, Pfister Bryan J
Department of Biomedical Engineering, New Jersey Institute of Technology, University Heights, Fenster Hall, Newark, New Jersey 07103, USA.
Rev Sci Instrum. 2019 Jul;90(7):075116. doi: 10.1063/1.5099633.
Blast simulators facilitate the creation of shock waves and measurement of pressure morphology in a controlled laboratory setting and are currently a vital model for replicating blast-induced neurotrauma. Due to the maintenance and operation cost of conventional blast simulators, we developed a pneumatic, table-top, gas-driven shock tube to test an alternative method of shock wave generation using a membrane-less driver section. Its unique operational mechanism based on air gun technology does not rely on a plastic membrane rupture for the generation of pressure pulses, allowing the simulator to be quickly reset and thus decreasing the experimental turnaround time. The focus of this study is to demonstrate that this proof-of-concept device can generate shock waves with diverse characteristics based on the selection of driver gas, driver pressurization, and driven section material. Pressure waves were generated using compressed nitrogen or helium at 15 psig and 80 psig and were analyzed based on their velocity and profile shape characteristics. At 15 psig, independent of the type of driver gas, driver pressurization, and driven section material, pressure pulses travelled at sonic velocities. At 80 psig, generation of shock waves was observed in all conditions. The choice of the driver gas affected the velocities of the resulting pressure waves and the shape of pressure waveforms, particularly the peak overpressure and rise time values. Our results demonstrate that depending on the selection of driver gas and magnitude of driver pressurization, the shock wave signatures can be controlled and altered using a piston-based driver section.
爆炸模拟器有助于在可控的实验室环境中产生冲击波并测量压力形态，目前是复制爆炸所致神经创伤的重要模型。由于传统爆炸模拟器的维护和运行成本较高，我们开发了一种气动台式气体驱动激波管，以测试使用无膜驱动部分产生冲击波的替代方法。其基于气枪技术的独特运行机制不依赖塑料膜破裂来产生压力脉冲，从而使模拟器能够快速重置，进而缩短实验周转时间。本研究的重点是证明这种概念验证装置能够根据驱动气体的选择、驱动增压和驱动部分材料产生具有不同特性的冲击波。使用15 psig和80 psig的压缩氮气或氦气产生压力波，并根据其速度和波形特征进行分析。在15 psig时，无论驱动气体类型、驱动增压和驱动部分材料如何，压力脉冲均以声速传播。在80 psig时，在所有条件下均观察到冲击波的产生。驱动气体的选择会影响产生的压力波的速度和压力波形的形状，特别是峰值超压和上升时间值。我们的结果表明，根据驱动气体的选择和驱动增压的大小，使用基于活塞的驱动部分可以控制和改变冲击波特征。
