I’m stating my experience. I’ve read about this for years here on these boards and my current shower make an ideal test situation. It’s 30" x30", only has the inside curtain and an open space above the curtain. I’ve taken note about how the curtain behaves at different water temps and in the normal course of showering I notice it as well. Sometimes I get bad headaches so occasionally at the end of a hot shower (which causes a lot of blow in) I turn the water to cold to run it over my head only. Invariably within a minute or so the curtain drops back down.
Missed the edit window, If you believe the second link, why would you think things have changed as per your OP?
How does that eliminate the factors in the vortex paper?
When I made the OP, I wasn’t aware of the vortex theory and experiments. Now I am. Actually I wasn’t aware of the “chimney” theory either.
My guess is it is a mix, and some of the factors I listed in the OP would affect the air flow in various ways, due to friction over surfaces, less “, vortexing” etc. I doubt a “typical” shower, each is probably different in significant ways.
Have you experimented while outside of the shower? You can destroy the vortex if you step into it, so if your position in the shower changes with the water temperature you have a confounding factor to address.
IME, the vortex’s suction is proportionate to how much water I force through my lo-flow showerhead. But stepping into the vortex itself tends to disrupt it completely.
Even without a steel tub, just the weight of the magnets may have something to do with it.
Just a comment. This post made me realize that although my shower curtain at my last residence blew inward it has not happened since I moved to my current residence 6 years ago. At least in the beginning, it was the same shower curtain, hooks, etc. The old place must have been haunted.
And I remember reading the Dope (or a Dope book) about the subject when I was living at the old place.
Bob
I’ll try it but I suspect people first noticed this effect while in the shower. Trying this outside of the shower seems like it’s trying to make the experience match the theory.