Material objects

Thermodynamic standard versions 1.0 and 1.1

All material objects for COFE and TEA support both CAPE-OPEN version 1.0 and CAPE-OPEN version 1.1 standard. More-over, conversions between the two standards are available and automatically applied. Conversions apply to property identifiers, property calculation routines, (two-)phase identifiers and overall calculations. For example, if a CAPE-OPEN version 1.1 property package is loaded into COFE, exporting phases GAS and LIQUID1, a CAPE-OPEN version 1.0 aware unit operation would obtain initial inlet values (pressure, temperature, overall composition) from the material object. If it would need vapor Gibbs free energy, it would call CalcProp on the material object specifying property gibbsFreeEnergy for phase Vapor. The COFE material would translate this into a CalcSinglePhaseProp for gibbsEnergy for phase GAS. The property package sets the values on the material object, the unit operation can obtain then; each using their own version of thermo dynamics.

Restrictions

The following restrictions apply to material objects:

• all supported properties (except for special properties temperature, pressure, flow, totalFlow, fraction and phaseFraction) must appear in props.ini in the proper format,
• composition derivatives for two-phase properties are not supported when using CAPE-OPEN version 1.0 thermodynamics,
• all material objects keep a single copy for pressure and temperature; in CAPE-OPEN version 1.0 pressure and temperature are only available for the overall phase. In CAPE-OPEN version 1.1, if pressure is specified for phase 1, and subsequently a different pressure is specified for phase 2, the latter pressure will apply to all phases. Implicitly this means that phase equilibria with different pressures for different phases (possibly appearing in porous media or particulate phases) are not properly captured by the material objects,
• flow and totalFlow are read/write for the overall phase, but read-only for all other phases,
• Total basis (or empty basis for extensive properties) are not supported,
• version 1.0 properties "mass" and "moles" are not supported,
• multiple vapor phases are not supported,
• if material objects are not released by the PMCs, the application will not exit.

See also: Property definitions