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by trollbridge 2 days ago
One of the problems with gasoline is its explosive nature, which the fuel storage and delivery system of a car attempts to mitigate. It has a better profile for burning off than a battery though since it will spill out and burn away from the vehicle.
2 comments
not_the_fda 2 days ago
Gasoline isn't that explosive. You can shoot up a gas tank and it will just burn. What you see on TV is movie magic. Gasoline vapor can explode, but you need the right air to fuel ratio and a spark.
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SV_BubbleTime 2 days ago
Uh… gasoline has a super high vapor pressure. If you start out at the wrong ratio, it does what it can to make that ratio right.

I’ve seen a few gasoline fires that start by burning, and then much more rapidly expressing potential.

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capitainenemo 2 days ago
Requires a good mix though. The parent is still correct. Mythbusters spent a long time trying to get cars to blow up in a dramatic hollywood fashion in various episodes and determined that under most conditions it wouldn't happen.

They did get it to happen, they just had to try really hard.

In most accidents the gas tank will not blow up.

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vablings 2 days ago
High velocity accidents where the gas is quickly dispersed into the air is pretty much the only way that happens.
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jojobas 2 days ago
Even then it's just a slow-burning fireball, not detonation, no shockwave.
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vablings 1 day ago
Still more than enough to burn your windpipe, skin to 2/3rd degree and permanently disfigure you
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leonidasrup 2 days ago
"Fast X: why cars don’t really explode when they crash"

"Petrol and diesel can only explode when under pressure and mixed with air and in the case of petrol, have a small amount of energy added in the form of a spark or a flame. Engines pressurise the fuel/air mixture in the cylinder and so produce small, confined explosions which turn a crankshaft and drive the wheels."

"When cars are involved in collisions, fuel lines are often torn and petrol leaks out onto a hot engine. Liquid petrol can catch fire in the presence of air. But it can’t explode because it’s not under pressure and is in the liquid phase rather than a vapour."

https://theconversation.com/fast-x-why-cars-dont-really-expl...

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