{"id":391425,"date":"2024-10-25T19:12:29","date_gmt":"2024-10-25T19:12:29","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/391425\/"},"modified":"2024-10-25T19:12:29","modified_gmt":"2024-10-25T19:12:29","slug":"391425","status":"publish","type":"reply","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/391425\/","title":{"rendered":"Reply To: Error Post-Processing Solution Data to Calculate Pressure and Viscous Forces"},"content":{"rendered":"<p>&lt;p&gt;Hi Rob, thanks for the reply!&lt;\/p&gt;&lt;p&gt;I performed some mesh refinement and ended up decreasing cell size on the walls by a factor of ten. Here&#8217;s a picture comparing the old mesh on the wall (on the right), and the mesh after decreasing cell size 5x, so the final mesh I tested has a wall cell size that is half of the left side of the picture. And all walls were refined, the image is just for a comparison.&lt;\/p&gt;&lt;p&gt;<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/10\/25-10-2024-1729883073-mesh refinement.PNG\" alt=\"\" width=\"523\" height=\"188\" \/>&lt;\/p&gt;&lt;p&gt;After running at the 10x refinement, Fluent gave me a net pressure force of 6.839022e-5 N and net viscous force of 4.0280261e-5 N. Exporting the solution data and performing the calculation described above gives me a net pressure force of 6.83902e-5 N and net viscous force of 3.95294e-5 N. This is about a 2% difference between the value I calculed and the value from Fluent, which is an improvement from the 5% from above. However, I still find it odd that I can only calculate the pressure forces (nearly) exactly and not the viscous forces. I also find it odd that the value seems to be converging towards the value I get when I export and calculate viscous forces, ie. the value from Fluent changed much more than the value I calculated when performing the mesh refinement. This seems to imply that exporting and calculating the forces is a better method since it might not require as fine of a mesh and it&#8217;s starting to take a while to create the mesh with the refinements.&lt;\/p&gt;&lt;p&gt;Again, thank you for the help and let me know if you have any more ideas about why I can&#8217;t get the values to match closer.&lt;\/p&gt;&lt;p&gt;Best,&lt;\/p&gt;&lt;p&gt;Kyle&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-391425","reply","type-reply","status-publish","hentry"],"aioseo_notices":[],"acf":[],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies\/391425","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/types\/reply"}],"version-history":[{"count":0,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies\/391425\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=391425"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}