{"id":362047,"date":"2024-04-13T00:39:58","date_gmt":"2024-04-13T00:39:58","guid":{"rendered":"\/forum\/forums\/reply\/362047\/"},"modified":"2024-04-13T00:39:58","modified_gmt":"2024-04-13T00:39:58","slug":"362047","status":"publish","type":"reply","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/362047\/","title":{"rendered":"Reply To: Reflected Mesh Refinement in Watertight Workflow"},"content":{"rendered":"<p>&lt;p&gt;Hi Rob,&lt;\/p&gt;&lt;p&gt;Thanks for taking the time to have a look at this.&nbsp; You have asked 2 very good questions which I think will help me understand bigger picture.&lt;\/p&gt;&lt;p&gt;I have purposely set the face size of the yellow strut in this example to the same as the horizontal plates.&nbsp; As noted there is minimal refinement compared to the opposite end.&nbsp; I am fine with this in principle &#8211; the flow is from left to right.&nbsp; There is separation at left side and for the velocities I am looking at the flow does not re-attach at right. But as you say the refinemement is a result of the settings on the struts.&lt;\/p&gt;&lt;p&gt;Secondly, the analysis is intended to parametrically look at the force on the struts for various size openings (solidity of strut). I was thinking of it this way &#8211; the force on the horizontal plates in almost a &#8220;constant&#8221;, and not of large concern.&nbsp; Yes there will be some boundary layer variation due to the recirculation between upper and lower plates due to solidity of the struts and resulting velocities, but I thought I could go coarser on the face sizing for the horizontals compared the verticals which will influence result more.&nbsp; Where the struts intersect the horizontals is perfectly as expected with the refinement at the corner.&nbsp; The issue the top most plate with the reflected refinement which I think is not required.&lt;\/p&gt;&lt;p&gt;To add, in order to test my concern I have been running a grid independence study varying the face sizing of the vertical and horizontal plates,&nbsp; but keeping rest of domain constant.&nbsp; I have been using total force in X-direction as the dependent variable.&nbsp; As I decrease the face size the total force increases, up to a point and then it begins to reduce.&nbsp; For example see below &#8211; horizontal axis is cell count and vertical is total force.&lt;\/p&gt;&lt;p&gt;<img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2024\/04\/13-04-2024-1712968383-P7.PNG\" alt=\"\" \/>&lt;\/p&gt;&lt;p&gt;So I&#8217;m thinking thios is pretty weird and needed to find an explanation.&nbsp; Are we seeing a variation in force due to the refinement of the top face cells?&nbsp; As we go to 4M cells, the top face becomes more consistent and uniform rather than banded as shown in my pics above which are from the 1.5M cell version.&lt;\/p&gt;&lt;p&gt;What I need to do is re-run the simulations to capture the X-force component of just the top plate to see how that varies with the mesh issues above.&lt;\/p&gt;&lt;p&gt;However if I could isolate that top face from the mesh refinement of the struts below and not have the banding would be awesome.&lt;\/p&gt;&lt;p&gt;Happy for your thoughts?&lt;\/p&gt;&lt;p&gt;&nbsp;&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-362047","reply","type-reply","status-publish","hentry"],"aioseo_notices":[],"acf":[],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies\/362047","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\/362047\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=362047"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}