Vessel Rupture Physical Explosion

Catastrophic rupture of a pressure vessel as a result of a PV rupture or physical explosion may also result in blast and fragment effects. 

Physical explosions are those in which no chemical or nuclear reaction occurs. The most frequent example is the rupture of a vessel whose contents, either gas or liquid, exist under high pressure. If the containing vessel bursts, its contents are free to expand and a shock wave is formed. Even a common automobile tire can explode if it is highly overinflated. 

This means "Boiling Liquid Expanding Vapor Explosion" and characterizes the physical explosion of a liquefied gas/supercritical fluid that is brutally decompressed to atmospheric pressure, in case of pressure vessel rupture or opening. Catastrophic BLEVE occurred when liquefied petroleum gases vessels burst (Mexico, Feyzin,...), followed by the "chemical" explosion due to gas cloud inflammation. In fact, this hazard is directly linked to metal weakening in case of fire around the vessel(s). It is the reason why it is recommended to install fire detectors that could order immediate depressurization of the whole plant in case of fire. 

A fire-induced BLEVE is a physical explosion that can occur when flame impingement locally overheats the vapor space of a storage vessel containing a liquefied material under pressure. As a result of the increased temperature, the vessel pressure will increase due to the higher vapor pressure. For vessels that lack adequate pressure relief, rupture can occur due to local overheating because the metal may be sufficiently weakened that it is unable to withstand even the normal vessel design pressures. When contents are noncombustible (e.g., water), a mechanical explosion (liquid expanding rapidly into vapor) will occur. When flammable, as with hydrocarbons, a fireball will also follow. 

A physical explosion relates to the catastrophic rupture of a pressurized gas filled vessel. Rupture could occur for the following reasons ... 

In general, physical explosions from catastrophic vessel rupture will produce directional explosions. This occurs because failure usually occurs from crack propagation starting at one location. If the failure were britde, resulting in a large number of fragments, the explosion would be less directional. However, the treatment of shock waves from this type of failure usually does not consider directionality. 

Physical explosion The catastrophic rupture of a pressurized gas-filled vessel. 

A Boiling Liquid Expanding Vapour Explosion, or BLEVE, is an industrial event related to the laboratory bump occasioned when the inadequately mixed bottom of a vessel of liquid becomes superheated, then explosively boils. In the industrial version, rupture of a pressurised container is usually involved. Although strictly speaking a non-reactive physical hazard, chemical fires and explosions, with fatalities, often follow. Means of estimating risk and prevention, with a fist of incidents are given[l], A more ferocious version, the Boiling Liquid Compressed Bubble... 

A nuclear explosion in a reactor is physically impossible because of the large t. Rupture of the reactor vessel or pressure tubes due to overpressure is also highly inq>robable because of a number of safety valves (not shown in any of the Figures). The steam produced can be dumped directly into the condenser or into the containment in case of emergency. All piping into the core has isolation valves, which can be closed. 

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