{"id":395955,"date":"2024-12-02T13:48:43","date_gmt":"2024-12-02T13:48:43","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/extremely-low-orthogonality-mesh-while-quality-is-satisfied-in-icem-cfd\/"},"modified":"2024-12-05T02:47:35","modified_gmt":"2024-12-05T02:47:35","slug":"extremely-low-orthogonality-mesh-while-quality-is-satisfied-in-icem-cfd","status":"answered","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/extremely-low-orthogonality-mesh-while-quality-is-satisfied-in-icem-cfd\/","title":{"rendered":"Extremely low orthogonality mesh while quality is satisfied in ICEM CFD"},"content":{"rendered":"

<p>Dear all,<\/p><p>I’m meshing a under-sea model whose domain extents is approximately 10 km x 6 km x 30 m on average. It’s really a large scale fluid domain with irregular seabed and shoreline. Due to high aspect ratio of domain, the model is literally like a sheet. <\/p><p>All structured mesh of hexahedron is considered. I have been working on repairing the negative element for quite a long time by checking determinant 2x2x2. I have applied Y-block and adjust the edge parameter (lower spacing near the irregular surface on the right side) to eliminate the negative element. And finally the top view of the blocks and the generated mesh are shown below. <\/p><p><\/p><p>The total element is 1.4 million. The value of determinant 2x2x2 is good. However, the minimum orthogonality is below 8e-3 which is unacceptable, I think, for FLUENT. The mesh is used and a preliminary steady single phase inviscid flow has diverged with increasing continuity residual. <\/p><p><\/p><p>The location of worse orthogonality element is near the irregular distorted surface on the right side as shown below. <\/p><p><\/p><p> <\/p><p>I thought that the divergence is mainly caused by the poor orthogonality of mesh and  tried several ways to improve the orthogonality but failed. I have try “smooth mesh globally” and “smooth hexahedral mesh-Orthogonal” function in Edit mesh panel to perform post processing of the mesh, the quality become even worse and negative element occurred. <\/p><p> <\/p><p>Are there any ways I can do to improve the orthogonality in ICEM?<\/p><p>Any suggestions would be greatly appreciated. <\/p><p> <\/p><p>Best regards<\/p><p>LEE<\/p><p> <\/p><p> <\/p><p> <\/p><\/p>\n","protected":false},"template":"","class_list":["post-395955","topic","type-topic","status-answered","hentry","topic-tag-fluent","topic-tag-icem-cfd-structured-mesh","topic-tag-large-models","topic-tag-orthogonality-1"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_forum_id":["27792"],"_bbp_topic_id":["395955"],"_bbp_subscription":["51510","199"],"_bbp_author_ip":["2001:250:3002:3270:884d:256d:a3f9:78a9"],"_bbp_reply_count":["4"],"_bbp_reply_count_hidden":["0"],"_bbp_voice_count":["2"],"_bbp_engagement":["51510","199"],"_btv_view_count":["521"],"_bbp_topic_status":["answered"],"_bbp_last_reply_id":["396350"],"_bbp_last_active_id":["396350"],"_bbp_last_active_time":["2024-12-05 02:43:41"]},"test":"bfdef4e41fe840e99014e0c0ef18055b3cd7380f"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/395955","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/types\/topic"}],"version-history":[{"count":1,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/395955\/revisions"}],"predecessor-version":[{"id":396351,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/395955\/revisions\/396351"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=395955"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}