I Why Does Fire Not Travel Backwards in a Gas Hose During Ignition?

AI Thread Summary
Fire does not travel backwards in a gas hose during ignition primarily due to the pressure of the gas or liquid pushing outwards, which prevents flames from entering the hose. Additionally, the lack of sufficient oxygen inside the hose inhibits combustion from occurring there. When the hose is ignited, the flame burns at the end where the gas meets fresh air, creating a barrier to reverse flame propagation. If the hose were to drip and create a pool of flammable liquid, there is a potential for flames to travel back if the conditions are right, but this is generally unlikely. Understanding these dynamics can clarify misconceptions often portrayed in movies.
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Hi , a simple question arose in my head , why is that every time I have seen a hose attached to a gas tank being set on fire the fire always burns out of the end of he hose but the fire never travels backwards inside the hose back to the tank to explode it.
the same I suppose happens to a gasoline pumps hose which you normally stick in your cars fuel tank , i assume if you would lite it on fire and hold it open the fireball would never travel back inwards into the hose.
Why is this so? is it because there is pressure and fluid/gas coming out so fire cannot get in or also because in the hose there is very little oxygen so the flame cannot go back more so it stays at the end of the hose where the fluid/gas stream meets fresh air (oxygen) ?

what happens when the pressure of the gasoline or gas ends up and the hose begins to drip could the flame catch backwards inside the hose then ? and travel to the tank and if there would be the right amount of fumes make it explode then ?

this has been shown many times in movies both correctly and incorrectly so i wonder.

thanks.
 
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I think it's easist first to watch a short vidio clip I find these videos very relaxing to watch .. I got to thinking is this being done in the most efficient way? The sand has to be suspended in the water to move it to the outlet ... The faster the water , the more turbulance and the sand stays suspended, so it seems to me the rule of thumb is the hose be aimed towards the outlet at all times .. Many times the workers hit the sand directly which will greatly reduce the water...
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