A head capacity table controls the flow rate based on the calculated pressure drop.
To define a head capacity curve:
Select the IndependentIndependent Variable: Flow Rate or Pressure.
By default, Flow Rate is the independent Variable, so Pressure is computed as a function of Flow Rate. This approach is consistent with the other resistance variation methods.
In some cases, however, the resultant pressure drop may be considerably different from the expected value. This may occur if flow recirculates through or near the resistance region. In some analyses, results have been improved by changing the Independent Variable to Pressure and re-running the analysis.