Numerical Study of Blast-Induced Primary Injury in Mosques: Identifying High-Risk Zones and Structural Implications

Ahmed M. Bagabir

Keywords: Blast-structure interaction, CFD, compressible flow, injury prediction, numerical analysis.

The present study employed numerical simulations to investigate the impact of blast waves on people praying inside a mosque. The study also investigated the influence of the location and intensity of the explosion. The inviscid Euler equations were solved numerically using a finite volume method. Dynamic mesh adaptation to coarse initial cells has proven suitable for predicting qualitative and quantitative flow features. It was assumed that explosives of different TNT equivalent weights (1.5kg, 2.5kg, and 5kg) would be detonated deliberately in two locations in the mosque: at the front and in the center. This is the weight of a typical pipe bomb or suicide explosive belt that can be carried maliciously. The flow visualizations are analyzed using a schlieren image. The time history of overpressure is monitored at several locations inside the mosque. The results reveal that the impact of explosions on the eyes, lungs, and brain varies depending on the location of the mosque. Blast waves from confined-space explosions are intensified by reflective surfaces. Individuals praying at the front and center of the mosque are assumed to be the primary targets and are more susceptible to inevitable death. However, those praying close to the reflective walls, particularly near the corners of the mosque, are at risk of primary injury due to the repeated reflections of the blast waves. The current findings will prove invaluable in the design of effective safety measures to mitigate the impact of explosions on people.

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