Mesh Interrogation

  V2K provides tools for the quantitative analysis of grid quality via the Grid Quality panel. This is available via the Solver panel in the main menu bar by selecting the Quality option. Note that one or more blocks must be selected for this option to become available for selection.
  Grid quality metric calculations involve one or more of the following on a per-element basis and are described below.

Quality Metric Calculation

Element Volume

 The Negative Volume check evaluates element volumes and compares each result against the threshold defined within the preferences panel when the Compute button is pressed. Results of this comparison are written to the scrolling text field within the panel. Two levels of output are available with the display based upon the setting of the View Details checkbox. For the detailed summary, maximum and minimum element volumes per block are printed along with the number and percentage of elements whose volume falls below the user prescribed threshold, otherwise a summary statement indicating whether or not negative volumes exist within the selectd block(s) is written.

Element Stretching

 The Stretching check examines the extent of the element stretching in each of the coordinate directions and compares this against the threshold defined within the preferences panel. The detailed listing of these calculations includes the maximum stretching detected in each direction within each selected block(s) along with the corresponding indices of the point at which it occurs. The total number of stretched elements is also printed per block. The abbreiviated summary provides an indication of whether or not any stretched elements were detected. It should be noted that stretching values are never less than unity, and the result for any calculation which yields a value less than unity is simply reciprocated.

 When the Stretching option is selected as the only quality check, the MG Level menu becomes sensitized allowing the user to select the refinement level of the mesh for which the stretching check is to be performed. A level of 0 indicates the original grid is to be examined while other values indicate a subset of the original grid as is defined in a multi-grid sense. Levels 1-4 are supported, and for the selected MG Level, the software examines the selected blocks to ensure that such are multi-gridable to the selected level before proceeding.

Element Skewness

 The Skewness check examines the extent of the element skewness and compares this against the threshold defined within the preferences panel. The detailed listing of these calculations includes the maximum and minimum skewness detected along with the corresponding indices of the element at which it occurs. The total number of skewed elements is also printed per block. The abbreiviated summary provides an indication of whether or not any skewed elements were detected.

Report Generation

 As an aid in report formal preparation, the contents of the text field may be redirected to a text file using the Save As... option within the File menu at the top of the panel. This displays the Quality Save As... output panel which permist directed output.