OML file format for Twin Activate / Compose (LookUp Tables ND)


From version 2020 onwards, Altair® Flux® can export simulation results as an OML file that may be used in Altair® Twin Activate® to create a Lookup Table ND. Assimilable to model reduction, this export can replace time-consuming Finite Elements co-simulation while keeping a very high level of accuracy.

This feature is available for all applications in the 2D, Skew and 3D modules of Flux. However, to generate this export, a parametrized scenario must be solved beforehand. Once integrated into a system application, the component allows the simulation software to take the Finite Element model into account by performing interpolations of the input and output values when requested.*

This export may also be used in Compose to apply a specific post-processing to the exported quantities (sensors, formulas and I/O parameters) in this file.

How to export an .OML file format for Twin Activate / Compose (LookUp Tables ND)?

To generate the export in Flux:
  • in the menu Data exchange, click on Export a data table;
  • select the format : .OML file format for Twin Activate / Compose (LookUp Tables ND);
  • choose the Destination directory for the creation of the OML file;
  • select the Input parameters of the file in the parameter list;
  • choose the Output parameters of the .oml file among the sensors and the I/O parameters ;
  • choose the type of value to export. To get all values, choose Current values.
Note: The name of the file is assigned automatically and is equal to the output parameter name.
Note: In the case of a multiparametric export, Flux creates one .oml file per output parameter.

How to use the exported OML file in Twin Activate?

To use this export in Twin Activate:
  • put the .oml files in the same directory of the Twin Activate project;
  • in the menu Diagram Home, choose the Context tab;
  • provide the name of the files created by Flux;
    Note: For example, if Flux exported the file TORQUE.oml, then only TORQUE should be written in Diagram Home (only one name per line).
  • verify in the menu Available variables of the Diagram Home if the variables were loaded correctly;
  • assign the variables to the LookUp Tables ND component.
    Note: The variable names (both inputs and outputs) are the same as in Flux.

How to use the exported OML file in Compose?

To use this file in Compose:
  • open this OML file with Compose;
  • all the formulas, sensors and I/O parameters are now available in Compose defined as vectors.


Export of N dimensions data table

Export FMU block

Flux-Activate co-simulation