Can venting areas mitigate the risk due to air blast inside railway carriages?

The influence of venting areas built from glass on the peak pressure and impulse of explosions due to high explosives is investigated. The pressure-time function of an air blast wave resulting from a high explosive is different from that of a gas or dust explosion. Its peak pressure is higher but the duration of the positive phase is much shorter. Its capacity of making a structure fly away is therefore reduced. Apart from the pressure-time function, it is shown that also the direction of the wave has an influence. Starting from a certain distance to the explosion, calculations indicate that the air blast wave inside a tubular structure becomes one-dimensional. In such a case, the influence of venting areas parallel to the wave propagation direction is small. This is shown in the study by several calculations using fluid-structure interaction. The pressure peak and the impulse are compared at selected points in tubular structure differing in the existence of openings, their dimension and position, and their number. Their effect is found to be small even in the case that the opening is near the explosion. In addition, the influence of venting areas in realistic train carriages is presented.

LARCHER Martin;  CASADEI Folco;  SOLOMOS George;  GEBBEKEN Norbert; 

2011-07-19

Multi Science Publishing

JRC62703

2041-4196,   

https://publications.jrc.ec.europa.eu/repository/handle/JRC62703,   

10.1260/2041-4196.2.2.221,