This widget allows to activate  very complex  coupled heat and mass 
tranfer model combined with humidity models (corresponding theoritical
 aspects have been proposed by Thierry Duforestel (EDF R&D)). 
Activating this check-box has two major effects 
on the SYRTHES graphical user interface: 
-  a new specific bloc of windows appears on the left part of the interface allowing to set conditions and on the other hand 
-  purely conduction windows are not accessible any more. 
 
SYRTHES conceptors  have tried to hide as much as possible 
the complexity of the proposed models by using a library of predefined materials
instead of proposing to set through the interface the material properties.
A possibility is given to add new materials in the library through specific programs
(see specific documentation for the adequate procedure).
Two major options are included: 
-  a model solving Temperature (T) and vapor pressure (Pv)
-  a model solving Temperature (T), vapor pressure (Pv) and total pressure (Pt), which is more complete and compulsory for some configurations 
 
Warning: Authors underline, that  these modelling may turn out to be be quite tricky 
 to use. For complex 
configurations, interpretation of results or of the behaviour of a computation are 
still reserved to specialists. Some particularly complex cases (especially when 
condensation is involved during rapidely changing transients) may sometimes require some tuning in some 
material properties or numerical parameters.
 ________________________
 SYRTHES version   : VERSION_SYRTHES
 Name help file  : Ho_Hm_ch.html
 I. Rupp, C. Peniguel  -  may 2014
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