Secondarily, should the fan be outside or inside the window?

Asking for a friend. (Me, help. I can’t remember physics, it’s too goddamn hot)

Edit: I’ve opened all the windows and set up a fan a short distance from the window pointing out and it’s reduced the temperature to near-tolerable levels. Unfortunately, venting through the attic was a no-go but moving things aside might make it an option next time. Thank you all, I appreciate the help!

  • Hacksaw
    6·
    5 months ago

    Most of the replies are correct overall. But Mattias Wandel had identified another important factor. Fans don’t just “stuck from the back” and blow out the front. They sort of suck from everywhere including the edges. This means that if you’re putting a fan right up against the window blowing in you’re sucking some room air as well. If you’re putting the fan right up against the window blowing out, some of the air you’re blowing out comes from outside in the first place.

    The ideal is then to blow out from 2-5ft away. This way all the air that’s blown is room air, and it’s all blown out. The venturi effect plays a small part. The Bernoulli effect? Equations? Explains why the air stays in a “tube” for a few feet away from the fan. Technically also explains the venturi effect… Everything is Bernoulli…

    https://www.youtube.com/watch?v=1L2ef1CP-yw