.MultiPhaseMixture.Information.ExternalPropertyPackages.CapeOpen

Information

The only currently widely adopted standard for thermodynamic property packages is the CAPE-OPEN Thermodynamic and Physical Properties. “CAPE-Open standards are the uniform standards for interfacing process modelling software components developed specifically for the design and operation of chemical processes” (Colan, 2015).

Tool Requirements

• Compiler: Visual studio 2010 or later
• Dymola 2015 or later
• Supported only for Windows (although CAPE-OPEN was intended as a cross-platform specification, in practice CAPE-OPEN is only supported on Windows)

CAPE-OPEN version

The CAPE-OPEN backend that has been developed supports both the 1.0 and 1.1 version of the specification.

Modelica Settings

Settings in MultiPhaseMixture.Templates.ExternalTwoPhaseMixture that should be used when creating a new Fluid.

• nP= the number of supported phases, currently all phase specification (which phases that are supported and their order) needs to be specified by the user)
• libraryName = "CapeOpen" followed by the property package that is used. E.g. libraryName = "CapeOpen.FluidProp Thermo System//PCP-SAFT"
• setupInfo="UnitBasis=2;CodeLogging=true"), UnitBasis=2 equals mass based units. CodeLogging enables logging to the specified log file

Example - DryAir mixture medium

See MultiPhaseMixture.PreDefined.Mixtures.CapeOpen.FluidProp.DryAir

Limitations

Following disadvantages with the CAPE-OPEN thermo interface should be considered (Szczepanski, 2013):

• Missing calculations of: critical properties, phase boundaries, phase stability test.  
• No support of flash derivatives (derivatives of flash outputs w.r.t flash specifications with phases in equilibrium)
• Single calculation, in some circumstances it would be useful to calculate properties for an array of inputs

Another disadvantage is that it contains several internal function calls which create an overhead in computation time. And although it was intended as a cross-platform specification, in practice CAPE-OPEN is only supported on Windows.

References

1. CAPE OPEN, Thermodynamic and Physical Properties v1.1, May 2011, Downloaded from http://www.colan.org