# Flow and Energy Balance Reporting

Submitted by boiler-maker on September 8, 2011 - 11:00

How can we obtain quantitative information on the input/output mass and energy balances on faces directly?

How can these be monitored as the solution proceeds as a check for convergence, (whether in a steady-state simulation or a transient case)?

Plotting residuals on a graph may be possible as indicated in the airfoil tutorial, but hopefully this is not the only way to get at these numerical quantities to be extracted in text form.

Same for scalar field information, such as temperature, pressure, etc.

I am looking for the equivalent what Fluent provides as flux reports, surface integrals, and volume integrals.

## Create Field and Variable Results

In Caedium you can create new results (fields and variables, e.g., integrals) as shown in the tutorial "Fluid Flow Around a Sphere: Theory Comparison."

Specifically for a face area average (e.g., phi = p):

BinaryphiMultiplyA = phi * AUnary Sum(phi * A)Unary Sum(A)BinarySum (phi * A)DivideSum (A)For a volume average replace A above with Vol.

For a volume (assuming incompressible flow rho = constant) flow average just create

Binary(U * A)Dot Productn = (U * A).n, then substitute phi = (U * A).n in the above average creation.Variables are single valued (as opposed to fields which are defined at each mesh point). For an example of a variable monitor (updated at each interval Substance->Solver->Iterations) see the lift and drag monitor in the tutorial "Flow Over a Rotating Wheel with Moving Ground."

For integrals use

Unary Sumto build your variable, e.g., Pressure Force = Sum (p * A)To extract text values from a monitor (make sure it has the focus) use

File->Exportwith type = CSV (Comma Separated Values)