Property definitions

COFE will only support properties that it knows of. This is because demands are put on the materials to be able to perform unit conversion on property values as well as property value storage. Therefore, COFE will need to know a number of details about the properties it is expected to support. These details are stored in the file props.ini in the COCO data folder.

props.ini is a tab delimited data file; each item is delimited from another item with a tab character. If you decide to modify props.ini, do it with care and back up the existing version before you begin. If COFE or TEA fail to read props.ini, the material will not be able to store any properties and simulation becomes imposible.

The first line is a header line. All other lines of text in props.ini describe one propery each. The following items should appear on each line.

property name 1.0

This is the CAPE-OPEN name of the property, as in the Thermodynamics 1.0 standard.

property name 1.1

This is the CAPE-OPEN name of the property, as in the Thermodynamics 1.1 standard.

description

A descriptive text of the property

default display

Determines the default way the property is displayed in the stream display. Combination of the values 1 (Overall), 2 (Vapor), 4 (Liquid) and 8 (Solid), so a value of 14 for Vapor, Liquid and Solid. Make the value a minus value to show the Pure rather than Mixture values.

class

Property class. Determines the dimension of storage for the property. Currently, the only defined classes are:

A: scalar for mixture, vector for pure; i.e. density

B: vector for mixture, vector for pure; i.e. fugacity

extensive

Determines whether the property is extensive (1) or not (0). For example, enthalpy is extensive, so a value of 1 for enthalpy.

canHaveTotal

Determines whether the property can be displayed for the flow (1) or not (0). For example, enthalpy can be displayed for the flow (J/s) or per amount (J/mol), so a value of 1 for enthalpy.

pureComponent

If non-zero, the property is only available for pure compounds, so not for a mixture. Allowed values are:

1: the property depends only on temperature, e.g. idealgasenthalpy

2: the property depends only on pressure, e.g. glassTransitionTemperature

IsTwoPhase

Zero for a single phase property, 1 for a two-phase property.

MassBasisDependency

The power to use for molar weight during mass conversions.

Pa, N, J, mol or kg, m, s, K

The power for each of these units in the dimension, i.e. density (mol/m3 or kg/m3) should have 1 for mol or kg or mol and -3 for m, with 1 for MassBasisDependency.

See alo: Material objects