Using Gas-Driven Shock Tubes to Produce Blast Wave Signatures

Kumar, Rubbel; Nedungadi, Ashish

doi:10.3389/fneur.2020.00090

“…Animal models of blast injury vary considerably in intensity, animal shielding, animal orientation, head fixation, and other parameters, and extrapolation from studies performed in rodents using blast tubes to human injury induced by real-world blast exposure is limited by several well-recognized factors 58 – 63 . In particular, the physical dimensions of the rodent skull render it difficult to accurately mimic the blast-induced transcranial pressure gradients that can occur in the human.…”

Section: Discussionmentioning

confidence: 99%

Blast-induced axonal degeneration in the rat cerebellum in the absence of head movement

Bishop

¹

,

Won

²

,

Irvine

³

et al. 2022

Sci Rep

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Blast exposure can injure brain by multiple mechanisms, and injury attributable to direct effects of the blast wave itself have been difficult to distinguish from that caused by rapid head displacement and other secondary processes. To resolve this issue, we used a rat model of blast exposure in which head movement was either strictly prevented or permitted in the lateral plane. Blast was found to produce axonal injury even with strict prevention of head movement. This axonal injury was restricted to the cerebellum, with the exception of injury in visual tracts secondary to ocular trauma. The cerebellar axonal injury was increased in rats in which blast-induced head movement was permitted, but the pattern of injury was unchanged. These findings support the contentions that blast per se, independent of head movement, is sufficient to induce axonal injury, and that axons in cerebellar white matter are particularly vulnerable to direct blast-induced injury.

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“…xation, and other parameters, and extrapolation from studies performed in rodents using blast tubes to human injury induced by real-world blast exposure is limited by several well-recognized factors [55][56][57][58][59][60] . In particular, the physical dimensions of the rodent skull render it di cult to accurately mimic the blastinduced transcranial pressure gradients that can occur in the human.…”

Section: Limitations and Conclusionmentioning

confidence: 99%

Blast-Induced Axonal Degeneration In The Rat Cerebellum In The Absence of Head Movement

Bishop¹,

Won²,

Irvine³

et al. 2021

Preprint

0

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Blast exposure can injure brain by multiple mechanisms, and injury attributable to direct effects of the blast wave itself have been difficult to distinguish from that caused by rapid head displacement and other secondary processes. To resolve this issue, we used a rat model of blast exposure in which head movement was either strictly prevented or permitted in the lateral plane. Blast was found to produce axonal injury even with strict prevention of head movement. This axonal injury was restricted to the cerebellum, with the exception of injury in visual tracts secondary to ocular trauma. The cerebellar axonal injury was increased in rats in which blast-induced head movement was permitted, but the pattern of injury was unchanged. These findings support the contentions that blast per se, independent of head movement, is sufficient to induce axonal injury, and that axons in cerebellar white matter are particularly vulnerable to direct blast - induced injury.

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“…Shock tube experiments and computational fluid dynamics (CFD) simulations have been widely applied to investigate the generation and behavior of shock waves as well as to determine the high speed flow characteristics of different working fluids at different boundary conditions (Kumar and Nedungadi, 2020;Singh et al, 2020;Khawaja et al, 2016;Kim et al, 2017;Rigas and Sklavounos, 2005). As an example, Kumar et al conducted a comprehensive CFD study to determine the effects of various design parameters (i.e.…”

Section: Introductionmentioning

confidence: 99%

“…As an example, Kumar et al conducted a comprehensive CFD study to determine the effects of various design parameters (i.e. membrane burst pressure, driven section length and driver gas) of an open shock tube with respect to the generated pressure wave (Kumar and Nedungadi, 2020). Among other findings, it was discovered that high membrane burst pressures do not influence the decay rate of pressure waves, where however the driver gas has a significant effect on the blast wave shape.…”

Section: Introductionmentioning

confidence: 99%

Analysis of pressure drop and blast pressure leakage of passive air blast safety valves: An experimental and numerical study

Brenner

¹

,

Jenni

²

,

Guyer

³

et al. 2022

Journal of Loss Prevention in the Process Industries

5

0

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The purpose of passive air blast safety valves is to protect people and technical installations in buildings or facilities. In case of explosions, e.g. due to technical failures in an oil-and gas refinery, the safety valve should close in milliseconds with the incident shock wave and substantially reduce the blast-pressure leakage into the building. On the other hand, the safety valve should exhibit a low pressure drop in normal operation in order to reduce the power consumption of the ventilators. One main difficulty in the design of such safety valves is to meet the minimum technical requirements, while ensuring the functionality in intrinsically different operating modes. Therefore, the present study proposes a target-oriented evaluation and optimization procedure for such devices, incorporating comprehensive numerical and experimental investigations. CFD, FEM and FSI analyses are regarded as an appropriate approach to predict valve performance parameters and to gain additional insights into the flow or structural behavior of the safety valve, which serves then as a basis for geometrical optimizations. The introduced procedure is exemplified on an existing passive air blast safety valve as a case study. The performance of the new design is significantly increased in ventilation operation, while meeting the performance criteria in the stress case when subjected to blast loads.

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Using Gas-Driven Shock Tubes to Produce Blast Wave Signatures

Cited by 18 publications

References 13 publications

Blast-induced axonal degeneration in the rat cerebellum in the absence of head movement

Blast-induced axonal degeneration in the rat cerebellum in the absence of head movement

Blast-Induced Axonal Degeneration In The Rat Cerebellum In The Absence of Head Movement

Analysis of pressure drop and blast pressure leakage of passive air blast safety valves: An experimental and numerical study

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