Results

What this step does

After a run. When a run ends, the program converts the solution to VTK and evaluates the quantities that need the fields: the area-weighted wall $y^+$ distribution and the wall area above the $y^+$ limit, the back-flow at each outlet, and a table of mean values per boundary patch. No report is written automatically.

Values. The headline value is the total-pressure drop $\Delta p_0$: the mass-flow-weighted mean total pressure of the inlets minus that of the outlets, averaged over the convergence window and quoted with the larger of the convergence tolerance and the measured uncertainty (Δp mean-stability tolerance). The pressure-drop item also gives the static pressure drop, the engine backpressure, the loss coefficients (referenced to the mass-weighted inlet dynamic pressure), the flow split per outlet and the branch pressure drops. Pressures are relative to the operating (ambient) pressure. Further value items: wall treatment, heat balance, and the CFD-to-acoustics coupling (which flow quantities the acoustic run used, and whether the acoustic result is older than the flow solution).

Charts and tables. Residuals, the $\Delta p_0$ history with the averaging window, port pressures, the $y^+$ distribution, a probe along a line and, for acoustics, transmission loss, return loss, band TL, insertion loss, radiated SPL and port powers. Every chart can be zoomed, switched to logarithmic axes, edited (titles, series, colours) and exported (PNG, SVG, CSV); the settings are saved per run. Tables can be filtered and copied. A chart, table or value list can be sent to the Postprocessing step. The acoustic pressure along a line is solved only when you press Compute, because each new frequency is a field solve (a few seconds each); frequencies already solved come back at once.

3-D plots. Static and total pressure and $y^+$ on the walls; velocity, pressure and temperature on a section; isosurfaces; streamlines and velocity arrows (still picture or animated); and the acoustic pressure at any frequency, re-solved on demand from the saved acoustic system, with a phase animation. Each plot has a colour map, a range and a probe, and can be exported as VTK. "Compare with" colours a plot by this run minus another run: per volume point when both runs share the mesh, otherwise by probing the other run's field.

Studies and other runs. A run selector shows the points of the project's flow-rate sweeps and mesh-independence studies, and other runs of the same CAD file, without changing the open project. Study items: the system curve $\Delta p_0(Q)$ with its fit $\Delta p_0 = aQ^2 + bQ$ (no intercept), $\Delta p_0$ against the mesh, and the GCI values (Mesh-independence study parameter).

Containers per physics. CFD holds the pressure drop, wall treatment, flow plots, residuals and the CFD quality checks (mesh gate and solution gate in one item). Thermal (heat transfer on) holds the heat balance, the wall temperature and heat flux plots and the thermal quality check (the energy balance). Acoustics holds the transmission and insertion loss, radiated level, port powers, the acoustic pressure on the model, the CFD-to-acoustics coupling and the acoustic quality checks. Each summary states that physics' verdict in one line, with a link to its quality checks; the quality-check items carry the number of failed and warning rows. When the pressure-drop mean converged but the residuals did not reach their target (verdict "completed with warnings"), the residual rows read "Not met" as warnings, as the verdict says, not as failures.

Model window. The model view's pop-out button opens it in a window of its own (a second screen, for example). A 3-D plot chosen in the main window is then drawn there, with its settings beside it; "Bring back" returns it.

Reports and Export. The Report menu holds "Generate full report" ("Regenerate full report" once one exists: it opens the report builder for title, project, author, company, logo, notes, the sections of each physics, a solver-and-methods appendix and saved views), "View quick report" (every physics of the run with the default options; made on first use) and "Save quick report". Both reports cover CFD, thermal and acoustic results alike, in one layout. The Export menu holds the result files and Open in ParaView.

Source

The pressure-drop definition and the averaging rule are described in Δp mean-stability tolerance. The 3-D plots read the solution converted by foamToVTK (OpenFOAM user guide, 2026).

Valid range

Fields in this step 21

Related 5

• Runstep.run
• Postprocessingstep.postprocessing
• Mesh-independence study parameterqueue.mesh_study.parameter
• Δp mean-stability tolerancesimulation_control.dp_plateau.tolerance_pct
• Target y+mesh.target_y_plus

References 1

1. OpenCFD Ltd. (2026). OpenFOAM user guide. openfoam.com. Web page