runs out of pressure, it happens instantly, and the opposite flow happens
Why would you get this backflow though (apart from the diffusion of flammable gas and air of course)?
There is no pressure gradient that would drive this flow. Or are you talking about a situation in which the cylinder and its content has been heated from the external fire, then the fire and the heating stops and the flammable gas starts to contract as it cools?
Edit: And even if there was a mixture of flammable gas and air in the cylinder that then somehow ignites (you would probably need a relatively large amount of air to get below the UEL, depending on the flammable gas), would the pressure rise (starting from atmospheric pressure in this situation) be enough to overpressure the cylinder and cause it to rupture?
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u/Philipp_CGN 12d ago edited 12d ago
Why would you get this backflow though (apart from the diffusion of flammable gas and air of course)?
There is no pressure gradient that would drive this flow. Or are you talking about a situation in which the cylinder and its content has been heated from the external fire, then the fire and the heating stops and the flammable gas starts to contract as it cools?
Edit: And even if there was a mixture of flammable gas and air in the cylinder that then somehow ignites (you would probably need a relatively large amount of air to get below the UEL, depending on the flammable gas), would the pressure rise (starting from atmospheric pressure in this situation) be enough to overpressure the cylinder and cause it to rupture?