Vents high-pressure structures

High-pressure structures are capable of withstanding pressures of more than 1.5 psig (0.1 bar gauge). The vent design is based on the definition of a deflagration index for gases or dusts ... 

A relatively small pressure can result in a very large force if it is applied over a large area. Inadequately vented atmospheric storage tanks may therefore rupture if, for some reason, e.g. a high inflow, they are subjected to a relatively low internal pressure. Large side-on structures, windows, etc. are particularly prone to damage from an explosion even at a significant distance from the epicentre. 

This keynote paper gives a general discussion of blast waves developed by high explosive detonations, their effects on structures and people, and risk assessment methods. The properties of free-field waves and normally and obliquely reflected waves are reviewed. Diffraction around block shapes and slender obstacles is covered next. Blast and gas pressures from explosions within vented structures are sumnarized. 

A cyclone separator suitable for to pressure venting scenarios should be very robust in design, because in the case of a high liquid entrainment in the vent stream the resulting momentum forces exerted on the structure can be strong. 

Even bringing in these cells into a level rack is problematic. The containers are constructively identical with those of the vented batteries. If a cell is first put down on the front crossbar before the cell is pushed to the back, tensions appear in the container and damage occurs in the structure of the plastic. This leads inevitably to rips in the container if the valve is put in too tight, which causes it to open because the inside pressure is too high. 

High gas temperatures iii the vent spaces of IET-3 and IET-6 (cuid video analyses) indicate that hot jets of hydrogen produced by debris oxidation in the cavity and subcompartment structures burned as a diffusion flame as it was pushed into the air/nitrogen atmosphere in the upper dome of Surtsey. The hydrogen combustion contributed significantly to containment pressurization. 

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