Impact Of Blast Wave Research Articles

Novel Model to Investigate Blast Injury in the Central Nervous System

Blast-induced neurotrauma (BINT) is a common injury modality associated with the current war efforts and increasing levels of terrorist activity. Exposure to the primary blast wave generated by explosive devices causes significant neurological deficits and is responsible for many of the war-related pathologies. Despite research efforts, the mechanism of injury is still poorly understood. To this end, we have established a novel ex vivo model for the direct observation and quantification of BINT at the tissue level. The model provides a quantifiable and reproducible method to illustrate the mechanism of BINT. Isolated sections of guinea pig spinal cord white matter were exposed to a supersonic shockwave using a blast generator with small-scaled explosives. The blast wave impact with isolated tissue was observed using focused shadowgraphy with a high-speed camera recording at 90,000 fps. Concurrently, functional deficits were measured by monitoring the production of compound action potentials using a double sucrose gap-recording chamber. Additionally, anatomical deficits were measured after blast exposure with a dye exclusion assay to visualize axonal membrane permeability. Our findings demonstrate that direct exposure to the blast wave compressed nervous tissue at a rate of 60 m/sec and led to significant functional deficits. Damage to the isolated spinal cord was marked by increased axonal permeability, suggesting rapid compression from the shockwave-generated high strain rates that resulted in membrane disruption. The model provides new insight into the mechanism of BINT and permits direct observation that may contribute to the development of appropriate treatment regimens.

A fuzzy set analysis to estimate loss intensity following blast wave interaction with process equipment

Blast waves are able to produce structural damage to process equipment even at great distances from the source point of an explosion. A loss of containment may follow and, if hazardous substances are released, relevant secondary scenarios may be triggered, resulting in domino effects. The present study was focused on the assessment of the expected structural damage and of the associated intensity of loss of containment of process vessels loaded by blast waves. Hence, a knowledge-based fuzzy set analysis was used to assess the expected overall probability of occurrence of different damage states defined for several categories of process equipment items. The fuzzy approach was also used to obtain specific threshold values for the escalation sequences (domino effects), taking into account the hazard due to the expected secondary scenarios caused by the loss of containment following blast wave impact.

Animating real‐time explosions

AbstractAny sufficiently powerful explosion in air creates an expanding blast wave that propagates outwards from the source. The paper explores the physically based simulation of a blast wave impact on surrounding objects. The emphasis is on simplifying the underlying physical and chemical governing equations in order to achieve a visually believable result that performs in real time. A connected voxel model is used to represent objects, so that realistic solid debris is generated instead of flat polygons. The model permits arbitrary voxel shapes, which allow the creation of more complex objects with a lower number of voxels when compared to models using uniform voxel shapes. This model also overcomes certain limitations of the spring–mass particle model when it comes to representing rigid bodies. The paper also explores auxiliary visual effects caused by the blast wave, such as flame, smoke and dust. Each of these cues increases the visual plausibility of the explosion being simulated without being rigorously physically based or computationally intensive. Copyright © 2002 John Wiley & Sons, Ltd.

Effect of angle of impact of blast wave on low-cycle endurance of steel 20 in working media

Effect of angle of impact of blast wave on low-cycle endurance of steel 20 in working media