[TRNSYS-users] stability criteria not fullfilled

["Hartl Michael" <Michael.Hartl@arsenal.ac.at>]

Dear TRNSYS-users,

 

I'm struggling to create some wall types for a multizone building.

 

I get the message:

 

"error creating the wall transfer function coefficients:

 

 stability criteria not fullfilled

 

 check layer definitions (thickness, ratio of conductivity/density)"

 

Of course, I have already re-checked the layer definitions.

 

This message appears for wall types with quite a massive layer (e.g. bricks 0.53m) and an additional insulation (e.g. up to 0.16m). Also it appears when modelling the uppermost slab with a layer of wood (e.g. 0.20m) and insulation (e.g. 0.16m).

 

Unfortunatelly I couldn't figure out yet how to create these kind of wall types without having the error message.

 

I appreciate any suggestions,

 

Michael