Thermodynamics - User-Defined Special Property Methods
You may use this window to define the user-defined special properties which may be calculated in unit operations which use the current thermodynamic system. Different sets of user-defined special properties may be defined for each thermodynamic system.
You must select the stream mixing methods to be used in calculating these properties in this window. User-defined special properties will not be calculated unless a method is selected here.
Global property data are entered in the Component Data Entry for Refinery Inspection and User-Defined Special Properties Window and/or in the Assay Data Entry for Refinery Inspection and User-Defined Special Properties Window. Data specific to this thermodynamic system are entered here.
User-defined special properties may also be printed in the stream property reports.
Usage
From the Thermodynamics - Main Window, select (highlight) the system for which modifications are to be made in the Defined Systems list box.
Push the Modify button to transfer to the Thermodynamic Data - Modification Window and press the User-Defined Special Properties button to open this window.
Select a property from the Property list in the first column of the table. You may change the name of a property by highlighting that row and pushing the Rename User-defined Special Properties button. This accesses the User-defined Property - Rename Window.
Method defines the method used to mix the component property values to produce a value for the stream. See Stream Mixing Methods for further information.
Basis specifies whether the component values will be mixed using their mole, weight or liquid volume fractions.
Blending defines the way in which missing data are handled when calculating properties from blended assay streams. The default component blend option for user-defined special properties is ”r;Zero”.
The Enter Data button allows data to be entered for this property for this thermodynamic system only. If you wish to enter data for all thermodynamic systems, use the Component Property Selection for User-Defined Special Properties Window.
Property data are entered in the Refinery Inspection and User-Defined Special Property Data Entry Window unless the User-Formula stream method has been selected when they are entered in the User Formula Data Entry Window.
Thermodynamic Method Selection for Refinery Inspection Properties