Swimming pool modeling issue

[Michael Hurd]

Good to know, perhaps it was something I unwittingly did differently.

[veitner]

I know it is coming from the pool area because both the concrete inner layer, mid layer and the insulation all are gaining moisture over time, there isn't enough moisture in one of those products to elevate the moisture in all 3. The concrete certainly cannot add moisture to itself. Additionally, since the mid layer of the concrete basically is locked down for moisture flow, it cannot be coming from the outer layer of the concrete or outdoors since the mid concrete layer is locked down. Those are my thoughts.

To verify the moisture is coming from the pool area you could modify the permeance (additional sd-value) of the inner surface. Did you watch the results using Animation1D? It might be helpful to switch from R.H. to vapour pressure inside Animation1D (Edit/Properties/Moisture/Humidity) to fully understand whats going on.

Best regards
Veit Eitner

[Michael Hurd]

inserting a low perm layer (.01 perms) on the surface does help but does not solve the issue. I switched the animation to vapor pressure but I'm not really sure what to look for/how to read what the pressure is doing.

[Michael Hurd]

I switched the film to the vapor pressure mode and the predominant drive into the layers that are gaining moisture seems to be from the inside of the wall. In the animation, does the length of the arrow show magnitude of the drive or the depth in the actual material(s)? Does the arrow have to fully cross a layer for the vapor drive to be going through a material and into the next layer?

[veitner]

I switched the film to the vapor pressure mode and the predominant drive into the layers that are gaining moisture seems to be from the inside of the wall. In the animation, does the length of the arrow show magnitude of the drive or the depth in the actual material(s)? Does the arrow have to fully cross a layer for the vapor drive to be going through a material and into the next layer?

The length of the arrow is scaled to it's maximum - either global or per time step (configurable on tab "/edit/properties/moisture/water_content"). Hovering the mouse over (stop film at desired time step) opens a hint-window showing its actual magnitude.

I'm not really sure what to look for/how to read what the pressure is doing.

Diffusive driving potential is the Vapour Pressure - which could be written as a function of R.H. and Temperature (R.H.=vp/vpsat(T) -> vp=R.H.*vpsat(T)).

Because of the "convenient" ambient tempurature at the inner side (the pool area) the vapour pressure gradient will force the diffusive flow towards the inside during a significant period of the year. Just a guess

Best regards
Veit Eitner