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Any errors in the Mesh would be reported at this time. Check the output and make sure that there are no errors reported.
Main Menu > Mesh > Info > Size
How many cells and nodes does the Mesh have? You can check this in the graphics window where the mesh should be displayed. If it is not, you can display the mesh by going to
Problem Setup > General > Mesh > Display
Define
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Governing Equations
Problem Setup > Models > Energy
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