{"id":37159,"date":"2019-08-14T17:23:32","date_gmt":"2019-08-14T17:23:32","guid":{"rendered":"\/forum\/forums\/topic\/residuals-and-convergence\/"},"modified":"2019-08-14T17:23:32","modified_gmt":"2019-08-14T17:23:32","slug":"residuals-and-convergence","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/residuals-and-convergence\/","title":{"rendered":"Residuals and Convergence"},"content":{"rendered":"

Hello, <\/p>\n

<\/p>\n

I know there are many posts about residuals and convergence, sorry to bring up another one…<\/p>\n

<\/p>\n

I am using a k-omega model and this is what my residual plot looks like:<\/p>\n

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\"\"<\/p>\n

<\/p>\n

I am not very experienced with Fluent, I just finished the Cornell series “A hands-on introduction to engineering simulations” and I guess I still need more practice. But would you mind helping me with the following:<\/p>\n

<\/p>\n

1. From this discussion (\/forum\/forums\/topic\/how-to-get-system-convergence\/?order=all#comment-7bb6d7e2-172d-49de-82e8-aaa90073b115<\/a>) I learned that there are scaled and non scaled residuals, and that I can monitor other variables to check convergence. Why is it the case that it is more difficult for the continuity residuals to achieve the target convergence in some cases? <\/p>\n

<\/p>\n

2. I am confused as to how the solver treats the values we input as convergence criteria. What I mean is does the solver tries to reach convergence “equally” or is there an existing “competition”: if for example I choose 1e-5 for continuity and 1e-3 for all the other, will the solver behave differently from a case where all the values would be 1e-3? <\/p>\n

<\/p>\n

3. I observed similar trends in this thread as well (\/forum\/forums\/topic\/convergence-of-steady-state-turbulent-airflow\/?order=all#comment-f8a999b3-4598-456c-9b6b-aa9d00b5fad6<\/a>)and found out that there are Fluent lectures available. Can anyone help me accessing them please? I could not find them on the website. Or is it part of the subscription? If so would you have resources that I could consult specifically about the topic of convergence?<\/p>\n

<\/p>\n

(Oh and I checked, the values for my average and maximum skewness are 0.23 and 0.87 respectively)<\/p>\n

<\/p>\n

Thanks!<\/p>\n","protected":false},"template":"","class_list":["post-37159","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_old_topic_id":["9334"],"_bbp_old_topic_author_name_id":["Anonymous"],"_bbp_old_is_topic_anonymous_id":["false"],"_bbp_old_closed_status_id":["publish"],"_bbp_author_ip":[null],"_bbp_old_sticky_status_id":["normal"],"_bbp_likes_count":["0","0"],"_btv_view_count":["13170"],"_bbp_subscription":["241027"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["37159"],"_bbp_forum_id":["27792"],"_bbp_engagement":["199","49550"],"_bbp_voice_count":["2"],"_bbp_reply_count":["2"],"_bbp_last_reply_id":["92279"],"_bbp_last_active_id":["92279"],"_bbp_last_active_time":["2019-08-16 06:13:31"]},"test":"97b26285be36cffb89250ea2490390f4a1c17239"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/37159","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\/37159\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=37159"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}