Step 9: Energy Balances Reporting

   ANSYS FLUENT can report the overall energy balance and details of the heat and mass transfer.

1.   Compute the gas phase mass fluxes through the domain boundaries.

Reports Fluxes Set Up...

(a)   Retain the default Selection of Mass Flow Rate in the Options group box.

(b)   Select air-inlet-4, fuel-inlet-5, and poutlet-3 from the Boundaries selection list.

(c)   Click Compute.

  The net mass imbalance should be a small fraction (say, 0.5% or less) of the total flux through the system. If a significant imbalance occurs, you should decrease your residual tolerances by at least an order of magnitude and continue iterating.

2.   Compute the fluxes of heat through the domain boundaries.

Reports Fluxes Set Up...

(a)   Select Total Heat Transfer Rate in the Options group box.

(b)   Select all the zones from the Boundaries selection list.

(c)   Click Compute and close the Flux Reports dialog box.

  The value will be displayed in the console. Positive flux reports indicate heat addition to the domain. Negative values indicate heat leaving the domain. Again, the net heat imbalance should be a small fraction (say, 0.5% or less) of the total energy flux through the system. The reported value may change for different runs.

3.   Compute the mass weighted average of the temperature at the pressure outlet.

Reports Surface Integrals Set Up...

(a)   Select Mass-Weighted Average from the Report Type drop-down list.

(b)   Select Temperature... and Static Temperature from the Field Variable drop-down lists.

(c)   Select poutlet-3 from the Surfaces selection list.

(d)   Click Compute.

  A value of 1297.46 K will be displayed in the console.

(e)   Close the Surface Integrals dialog box.