A demonstration of the stack effect in fires There is difference in indoor-to-outdoor air density, this is because of temperature & moisture differences The greater the thermal difference and the height of the structure, the greater the upwards force

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See also the "trench effect " as discovered in the King's Cross tube fire. If the tube is inclined at the correct angle the fire jet gets a runaway effect.

The fire desperately seeks oxygen to fuel itself. Like a swimmer in a deep pool. When O2 gets low you get motivated to reach the surface fast

Yea this is how it works. I actually have something like this on my balcony in small size and use bio ethanol gel for it. It's from the brand Höfats. Looks great.

Explains my farts

Of course fire will move towards the supply of fuel, oxygen in this case.

That’s a beyblade

@SaveMyVideo

Very interesting 👍

Awesome demonstration!