CoolProp  6.6.0
An open-source fluid property and humid air property database
Namespace List
Here is a list of all namespaces with brief descriptions:
[detail level 123]
 NCoolPropCode for all the binary pairs in the mixture
 Ncpjson
 NHumidAir
 NODEIntegrators
 NUNIFAC
 NUNIFACLibrary