Reduced Order Model, ROM

The Reduced Order Model is a feature that predicts results for arbitrary conditions based on results calculated via batch run.

It analyzes data using Proper Orthogonal Decomposition (POD), creates a Reduced Order Model (ROM), and then uses this to generate 3D results for input conditions.

The generated results are in the same format as the computed results and are treated identically to the results from the batch run, being added to the batch calculation conditions.

It consists of two parts: ‘Build Model’ and ‘Reconstruct from Model’.

Build Model

Clicking the ‘Build ROM’ button opens a new window where you can select the conditions from the batch run to use when creating the ROM. Use the mouse to select the desired conditions (use Ctrl-A to select all) and click the Add button.

Build ROM window

Pressing the OK button displays a window for selecting variables to use in ROM creation. All variables from the Excel or CSV file read during batch run conditions appear on the left; select the parameters to use from these. The Excel or CSV file may contain numerous variables not relevant to the calculation conditions. If these are not excluded, the ROM will not predict results accurately.

Select parameter window

Pressing the OK button creates the ROM, and the selected conditions are displayed in ‘Snapshot Cases’.

Reconstruct from Model

For each parameter selected for ROM creation, set the conditions by moving the slider bar or entering a value. Enter the desired name in ‘Case name’ and click the ‘Reconstruct case with ROM’ button to generate the prediction results.

The generated result is added as the ‘Case Name’ in the ‘Run’ – ‘Batch Cases’ window. The added result is treated identically to other calculated results.

Right-clicking the created result and selecting ‘Load’ allows post-processing. Selecting ‘Open in ParaView’ from the menu opens this result. Right-clicking and selecting ‘Schedule Calculation’, then pressing the ‘Start Calculation’ button, initiates the calculation using the predicted result as the initial condition.