Why does a flamethrower not explode?

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A flamethrower does not explode because the fuel it expels lacks an oxidizer, which is necessary for combustion, preventing the flame from traveling back to the fuel container. Additionally, the speed of the fuel stream is greater than the rate at which the flame can propagate, ensuring the ignition point moves away from the operator. These two factors work together to maintain safety during operation. Understanding these principles clarifies why flamethrowers can function without risk of explosion. The design effectively mitigates the potential for backfire incidents.
lokifenrir96
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To be more specific, why is it that when the flammable gas or liquid is pumped through the barrel and ignited at the end of the barrel, the flame does not spread backwards along the stream of liquid/gas into the fuel container and cause an explosion?

Is it simply because of the high pressure at which the fuel is pumped out? Or is there another reason, or a safety mechanism to prevent this from occurring?

Thanks!
 
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Two factors. Most important is that fuel in flame thrower doesn't contain oxidizer. It needs oxygen in air to burn. So it can't burn until it is expelled.

Second is that the stream typically travels faster than flame can propagate along the stream. So the ignition point is actually carried away from the operator.
 
Well-explained, thanks!
 

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