Blend rules

Use blend rules to linearise property values prior to regression and export.

A blend rule converts a non-linear blending property into an indexed property, which can be blended linearly, that is, blended by combining the weighted average of the indexed property value for the stream components.

When a blend rule is associated with a property, a new indexed prediction is added to the predictions list for that property. This value is the indexed value for the source property value. By default, the original property value is deactivated as a prediction, and the new indexed value becomes a prediction. During calculation Process Model Manager Reference Manual will calculate the indexed property value using the formula associated with the blend rule, and these indexed values will be used for regression to calculate the process model output. Hence the process model will output the indexed property value, and not the true property value. If the blend rule is added before the property, then when the property is added as a driver an Indexed option is available to use the indexed value of the property as a driver rather than the real property value ("Add Input Properties Parameters" on page 108).

Note: Only administrators can create blend rules, and publish them using CrudeSync. Once published, the blend rules can be downloaded and synchronised with the rules already present in Process Model Manager Reference Manual.