Initial Condition and State
Source
Source is a volume condition for a species referring to selected volumes. If you select Create a New Source option under the Species module, you can introduce the concentration sources and total concentration sources into a selected volume.
1. No — Source term is zero in the species transport equation.
2. Concentration Source Per Volume — Allows you to specify the net rate of scalar per unit volume per second.
3. Total Concentration Source — Allows you to specify the net rate of scalar over the entire volume per second.
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Multiple sources are numbered sequentially, such as Source 1, Source 2, Source 3. If you remove a source, the remaining sources are renumbered starting at 1.
Initial Condition
Initial Condition refers to the values of the independent variables required to start a simulation when you select Start from Initial Values in the Run group. You can also start a simulation using Start from Solution or Continuation Run. In these instances, the Initial Condition set under the volume are not used. For the Species module, you can specify the initial values for each Volume of scalar under Specified Value.
State
The State of a volume within the Species module determines whether the scalar transport equation is solved (Active) or not solved (Blanked) within that volume. Setting the State of a volume to Blanked is equivalent to freezing the species at its initial value.
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For a selected volume, the State in the Species module is independent of its state in other modules. For example, if you set the Flow module to Blanked that makes a volume solid, then you can set the Species module to Active or Blanked.