I'm making some shots in the dark (I don't have any experience with this), but two possibilities come to mind for me.
- Something similar to a dryer vent going throug a window. I've seen where they're replaced the glass with a tin-like pane.
- Is there any type of stove hood that you could rig up that has the vent go out the window? It could be like above where the glass is replaced with a metal pane of some sort.
Like I said, these are just some wildass guesses.