Additional Variables are variables that are added to a case to provide utility not offered by solution variables.
There are three basic types of Additional Variable:
A non-reacting scalar component that can be transported through the flow
Such an Additional Variable can be solved either on a per-unit-mass basis or on a per-unit-volume basis.
A scalar or vector variable with its value (or each component) defined by an algebraic expression
A Dynamic Variable that serves as a dimensionless CEL parameter that changes value several times during solution convergence, used in steady-state cases and harmonic balance cases
Dynamic Variables are used to change expression-based settings gradually, so as to maintain solution stability during convergence.
Modeling information for Additional Variables is available:
Implementation information for Additional Variables in multiphase flow is available:
This chapter describes the procedure for creating an Additional Variable and the user interfaces used to define and apply Additional Variables: