COCO - CAPE-OPEN to CAPE-OPEN simulation environment

Property tester

The property tester is a unit operation that just copies the inlet stream to the outlet stream. It has one inlet and one outlet. During the copying, it will query the inlet material for all property definitions and phases.

Version 1.0 testing

Version 1.0 property testing uses CalcProp with 'pure' and 'mixture' calculation type specifications for all combinations of properties and phase. It will attempt evaluating derivatives (Dtemperature and Dpressure, and for mixture type only: DmolFraction) and compare all obtained derivate values to values that have been obtained by perturbation. Warnings are generated in case of discrepancies.

Version 1.1 testing

Version 1.1 property testing will obtain lists of all pressure dependent, temperature dependent, single-phase and two-phase properties. It will evaluate all pressure dependent and temperature dependent properties, all single-phase properties for all phases that pass CheckSinglePhasePropSpec, and all two-phase properties for all combinations of phases that pass CheckTwoPhasePropSpec. All relevant derivatives are evaluated and tested against values that are obtained by perturbations. Warnings are generated in case of discrepancies.

Composition derivatives

Values of composition derivatives obtained by perturbation of principle composition directions and those obtained by evaluation of property.DmolFraction may not match in the material object or property package normalizes the compositions.

Test results

The results will appear in a report. For convenience, the tab separated results table will also be copied to the Windows clipboard, ready to be pasted in a spread sheet application for further inspection.

Test options

Relative perturbation distances and discrepancy tolerance can be specified. By default, a warning is produced for values that have a finite perturbed derivative, but the derivative could not be obtained from the material. This option however can be turned off.

All mass/mole-based property tests are by default performed with basis 'Mole'. This can be changed to basis 'Mass' as to subject all the material object's mass-conversions to testing.

The property tester does not have a graphical user interface page that allows changing the above parameters; use the interface supplied by the COSE to change the testing parameter values.

The thermodynamic that apply to the inlet are used for all property testing.