Sketch Units

All sketch data and parameter entities are handled according to the current unit system. All dimension values, variable manager values, and sketch entity data like line length, circle radius, or point position are appended with the current units system.

The default unit system is MMKS (mm kg N s). Opening or importing previous HM files containing sketch data are interpreted with this default unit system. Unit systems can be changed from Preferences > Sketching > Units.

  1. When opening/importing CAD data into a session, you need to choose your target units as what is set in the sketching units.
  2. When the sketching unit system is changed, all the sketches and parameter data present in the session are scaled based on the unit system value, including its realized lines and surfaces.
  3. Units can not be changed while sketching is in progress.

Use the Scale sketch data preference option to change the sketch data of your choice with or without scaling the data. Scale sketch data can be changed from Preferences > Sketching > Scale sketch data.

The Scale sketch data option is useful for legacy files, especially when there are no units. Previously, you would use unitless numbers. Now, you can change the units (for example, mm to cms or cms to mms) without scaling the model by selecting the Scale sketch data option.
Note: If you have two models with separate units, it is not recommended or then we do not recommend and support importing mixed units models. Instead, you should bring the models to common units in separate HyperMesh sessions, save the file with consistent units, and then import these models.

Grid Spacing

Grid spacing is interpreted from the values specified and the selected unit system.

HyperMesh CFD has five progressive levels of grid spacing, available in Preferences > Sketching > Grid Spacing. To change the default spacing for a particular grid, enter a value in the text box. Grid spacing for metric and English unit systems are maintained separately.