Tools → Workflows → C-NCAP VTC Quality Criteria
The C-NCAP VTC Quality Criteria workflow tool is part of the virtual testing protocol and allows you to perform the quality checks outlined in section H.1.1(f) of the C-NCAP Far-Side Occupant Protection Protocol.
In T/HIS, this tool displays the results and graphs required for the Simulation.
In PRIMER, we set the tool up by selecting the model unit system, selecting the Dummy Parts and H-point History Node.
How to use the Workflow Tool in PRIMER
When this tool is initially launched, the tool will attempt to collect all previously saved data from the Automotive Assessents Workflow.
The GUI will look something like this by default:
Model Unit System
Select the unit system of your model.
Display Time Unit
Select the display time unit for the graph outputs, either Seconds or Milliseconds.
Display Energy Unit
Select the display energy unit for the graph outputs, either Joules, Millijoules, Kilojoules or Foot-Pounds.
Dummy Parts
Select the include file containing the Dummy by pressing the right arrow for selection and picking options or manually type in the textbox.
H-point History Node
Select the DATABASE_HISTORY_NODE matching the H-point Node of the Dummy by pressing the right arrow for multiple selection and picking options or manually typing in the textbox.
Saving
Save the Workflow data to a .json file or save it to your model and then write the keyword file from PRIMER.
How to use the Workflow Tool in T/HIS
When this tool is initially launched, the tool will perform the quality checks automatically.
Once the run has completed the GUI will look something like the following image by default, with 4 checks presented on it's own graph on a single page.
For a full breakdown of each graph and it's results please see 'Understanding Each Graph and the Results' further down this manual.
Write Results
Writes the results out as displayed in the table in CSV format.
Model Unit System
Displays the unit system that has been selected in PRIMER for this model.
Reset Graphs
Reproduces the graphs and resets them to default settings.
Curve Labels Off
Turns off the labels written on the curves, to make them re-appear, then 'Reset Graphs'.
Datum Labels Off
Turns off the Datum Labelsto make them re-appear, then 'Reset Graphs'.
How to use the Workflow Tool in REPORTER
- Within the Automotive tab in REPORTER, select the C-NCAP VTC Quality Criteria template. It can be found by filtering for 'Virtual Testing’.
- Once open you will be prompted to select the Ansys LS-DYNA keyword file of the job you wish to post-process.
- You will then be asked whether you want to continue with the default results and output directories or configure them in PRIMER.
- On the first page an overview of the results will be presented in a table format much like the GUI output when running the Workflow manually in T/HIS. On the remaining pages you can see each 'Check' one by one with its results in more detail.
Understanding Each Graph and the Results
Full Setup: Hourglass Energy Compared to 10% of Maximum Internal Energy
The hourglass energy of the system should not exceed 10% of the internal energy of the system.
In blue colour, the internal energy of the full setup is displayed (only if the check is a fail).
The datum line is drawn at 10% of the maximum internal energy.
In foreground colour, the hourglass energy of the full setup is displayed.
For this check to pass, the peak of the hourglass energy curve must be within the green zone.
The limit and result are displayed in the table.
Dummy: Hourglass Energy Compared to 10% of Maximum Internal Energy
The hourglass energy of the dummy model components should not exceed 10% of the dummy’s internal energy.
In blue colour, the internal energy of the Dummy is displayed (only if the check is a fail).
The datum line is drawn at 10% of the maximum internal energy.
In foreground colour, the hourglass energy of the Dummy is displayed.
For this check to pass, the peak of the hourglass energy curve must be within the green zone.
The limit and result are displayed in the table.
Full Setup: Percentage Added Mass
At the beginning of the calculation, the increase in the mass of the overall model due to mass scaling should be less than 5% of the total mass of the model.
In foreground colour, the percentage mass increase is displayed.
The datum line is drawn at 5%.
For this check to pass, the peak of the percentage mass increase curve must be within the green zone.
The limit and result are displayed in the table.
H-Point: Z Displacement in the First 5ms of the Simulation
Within the initial 0 to 5 ms of the calculation, the H-point Z displacement should be less than 10 mm.
In foreground colour, the Z displacement of the H-Point Node is displayed, zoomed in to the first 6ms.
The datum line is drawn at 10mm.
For this check to pass, the peak and trough of the Z displacement curve must be within the green zone within the first 5ms.
The limit and result are displayed in the table.
