When we start a fire in our woodstove, there is often a short, quick “woosh” when the tinder or kindling catch. Then there are the regular crackles and pops of moisture and sap burning, and the settling of the woodstove and stovepipe as they heat up. But I don’t know why it wooshes.
In: Physics
The air around it heats up. Hot air rises. The hotter the air, the more and faster it rises.
A large fire makes that whooshing sound because whatever air isn’t consumed to feed the fire heats up and rushes upwards with the smoke. This is also the type of feedback that can lead to a firestorm, as the air rushing upwards cools, come backs down, and creates convection thus fueling the fire.
Look up the firebombing of Dresden for a good study of how this happens. Lot of people can die super fast when that happens.
Edit: found a story on it. Good read
https://www.latimes.com/archives/la-xpm-1995-02-10-mn-30388-story.html
Edit edit: here’s some basic stuff on firestorms
https://en.wikipedia.org/wiki/Firestorm
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