The FE Modeler Mesh Metrics tool allows you to test and evaluate the mesh quality of a model to avoid inaccurate or incomplete solutions. This tool performs shape testing for all continuum elements (2-D and 3-D solids, 3-D shells). This testing is performed by computing shape parameters, such as Jacobian ratio, which are functions of geometry. The following element shape parameters are available to display in the Mesh Metrics tool:

Accessing Mesh Metrics

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Once a model (ANSYS archive, NASTRAN, ABAQUS, or Simulation) is imported, you access the Mesh Metrics tool from the Insert drop-down menu, as shown below, or by using the context sensitive (right-click) menu.

The illustration shown below displays an example of Mesh Metrics elements as displayed in the tree. You can select these individual elements and then create components that meet specified criteria.

Once inserted, and the Mesh Metrics tree object is selected, a bar chart is displayed, as illustrated below. The chart is labeled with color-coded bars for each element shape represented in the model’s mesh.

The Details View allows you to change the type of mesh metric being displayed. For the illustration shown below, the Quality Factor Range is selected. The Quality Factor Range displays the minimum and maximum value over the entire mesh. Negative metric values are highlighted to indicate possible problem areas.

The Displayed Metric Range detail allows you to enter a range for the metric to display and display only the elements that meet this criteria. You can also select individual bars from the chart and display the elements that meet the criteria values covered by the selected bars. In this case the Displayed Metric Range detail indicates the range of the displayed metric.

The X-axis represents the value of the selected mesh metric and the Y-axis represents the percentage of the volume of the model represented by each bar. The graph can be filtered based on bodies (from Simulation) and element shapes. The height of a bar in the chart can represent either the number of elements or the percentage of the total volume represented by the elements that have a particular quality factor range. For example, a model could have a large number of poorly shaped elements that are confined to a small local area. The total volume of these elements might not be significant compared to the volume of the entire model. As a result, the bar corresponding to this low quality factor may not be significant. The mesh metrics tool displays one of the metrics shown below without qualifying the elements for acceptability. Details of how the various mesh metrics are calculated are given in Details of Element Shape Checking.