{"id":326527,"date":"2023-12-05T22:30:34","date_gmt":"2023-12-05T22:30:34","guid":{"rendered":"\/forum\/forums\/topic\/non-expected-gas-fraction-in-cells-near-a-wall\/"},"modified":"2023-12-05T22:30:34","modified_gmt":"2023-12-05T22:30:34","slug":"non-expected-gas-fraction-in-cells-near-a-wall","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/non-expected-gas-fraction-in-cells-near-a-wall\/","title":{"rendered":"(non-expected) gas fraction in cells near a wall"},"content":{"rendered":"<p>Hey all,&nbsp;<\/p>\n<p>I am modelling mass transference between phases and as I couldnt get the simulation to converge I started to &#8220;&#8221;debug&#8221;&#8221;. Although, I am not entirely sure this is the source of my convergence problem, it is something that I would like to know how to fix it.&nbsp;<br \/>It is an eulerian-eulerian simulation where liquid is primary phase and gas the secondary phase. I already tried several things, but the picture below is the result of solving only the primary phase (disabing the vof equation and the gaseous species) and as soon as that converged I just inserted at the inlet a gas fraction of 1e-7 and calculate my solution again.<\/p>\n<p>All the domains are porous (but I am not sure that is important here). But as you can see, without having any kind of gas source terms, those cells near the wall take values quite different from the others. The reason why I think this is a problem is that as soon as I activate source terms for the gas phase those cells will have values quite different from all the others bringing instabilities to the calculation (I believe). Does anyone have any inputs of a possible reason?&nbsp;<\/p>\n<p>I already changed the mesh but the gas fraction arose again on those last cells.<\/p>\n<p>Thanks in advance!&nbsp;<\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/12\/05-12-2023-1701815292-mceclip0.png\"><\/p>\n","protected":false},"template":"","class_list":["post-326527","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["267145","199"],"_bbp_author_ip":["23.206.193.146"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["137"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["326527"],"_bbp_forum_id":["27792"],"_bbp_engagement":["199","267145"],"_bbp_voice_count":["2"],"_bbp_reply_count":["9"],"_bbp_last_reply_id":["326722"],"_bbp_last_active_id":["326722"],"_bbp_last_active_time":["2023-12-06 17:05:22"]},"test":"ag14wret-aau-dk"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/326527","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":0,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/326527\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=326527"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}