{"id":381264,"date":"2024-09-01T05:45:10","date_gmt":"2024-09-01T05:45:10","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/convergence-issue-in-pipe-flow\/"},"modified":"2024-09-01T05:45:10","modified_gmt":"2024-09-01T05:45:10","slug":"convergence-issue-in-pipe-flow","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/convergence-issue-in-pipe-flow\/","title":{"rendered":"Convergence issue in pipe flow"},"content":{"rendered":"<p>&lt;p&gt;Greetings everyone. I am a new user of Ansys and I have very little knowledge about that software. Currently, I am trying to perform a simulation of laminar flow through a blind wye pipe as you can see in image 1. The diameter of the pipe is 1 meter and I have set the kinematic viscosity as .001 m\/s. In the inlet, I have inserted a parabolic velocity profile. The outlet boundary condition is set to outflow. I have used transient laminar model for solution. Now the issue is, when, my average velocity is 0.5 m\/s (Max velocity- 1m\/s), the Reynolds number is 500 and the solution converges like image 3. But when the average velocity is 1 m\/s (max velocity- 2 m\/s), the Reynolds number is supposed to be 1000 and this time the solution doesn&#8217;t converge (image 2) if I use the laminar model. Why does that happen? Is is cause the recirculation of fluid in blind part causes the flow to go turbulent? And even if it does, how can I know upto which inlet velocity, the flow remains laminar? And also how can I determine the Reynolds number where the flow suddenly become turbulent although it started off as laminar?<img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/09\/01-09-2024-1725169178-Screenshot 2024-08-30 131925.png\" alt=\"\" \/><img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/09\/01-09-2024-1725169384-Screenshot 2024-08-30 131110.png\" alt=\"\" \/><img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/09\/01-09-2024-1725169277-Screenshot 2024-08-30 131832.png\" alt=\"\" \/>&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-381264","topic","type-topic","status-publish","hentry","topic-tag-cfd-fluent","topic-tag-convergence-issues-1","topic-tag-laminar-pipe-flow-1"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_author_ip":["103.94.134.112"],"_btv_view_count":["276"],"_bbp_topic_status":["unanswered"],"_bbp_subscription":["199842","449341"],"_bbp_topic_id":["381264"],"_bbp_forum_id":["27792"],"_bbp_engagement":["199842","449341"],"_bbp_voice_count":["2"],"_bbp_reply_count":["5"],"_bbp_last_reply_id":["381844"],"_bbp_last_active_id":["381844"],"_bbp_last_active_time":["2024-09-08 14:28:04"]},"test":"evanmehedihasangmail-com"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/381264","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\/381264\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=381264"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}