In this node, you may define derived quantities that are calculated as a function of the compounds, pseudo-compounds and/or previously defined derived quantities. The definition of the derived quantities is similar to the pseudo-compounds, but derived quantities do not affect the reaction rates.
When doing parameter estimation, the derived quantities may also be reconciled, if you have experimental data available for them.
Derived Quantities Definition
This grid contains the list of Derived-Quantities and a
Preview Pane for the selected one.
You may add or edit the name, defining equation type and constant term for each derived quantity. The grid columns are organized as follows:
- The Derived Quantity column is used to enter the Derived Quantity name. It can be renamed by editing this field.
- The Type column is to select what type of equation will be used to calculate the derived quantity.
Two options are available, and the general expression for each of them are:
- Linear Sum:
- Nonlinear Product:
Where Constant and coeffi and expi are numerical values entered by the user that represent the Constant Term, Coefficients and Exponents respectively, while Ci can be the concentration in a given phase or the total moles for a given compound, or a previously defined pseudo-compound or derived quantity. Please be aware that the concentration for the compounds are selected to be either Molarity or Partial Pressure in the Units Configuration node.
- The Constant Term column is to enter the constant for both types, Linear Sum and Nonlinear Product. The default value is 0.
- The Expression column (Read-Only) displays derived quantity formula.
- The optional Units column is a text field (maximum 50 characters) used to define units for each Derived Quantity. The units defined here are shown in other nodes where the Derived Quantities are displayed.
- The Notes column (Optional) is a text field (maximum 100 characters) used to store comments about the derived quantities.
Adding a Derived Quantity
- In the last row, enter the name of the derived quantity. The row will change to edit mode, and you may save this new derived quantity with the <ENTER> key or clicking on the pencil icon in the row header.
Deleting a Derived Quantity
- Select the derived quantity row and use the <DELETE> key.