{"id":346215,"date":"2024-01-23T16:47:11","date_gmt":"2024-01-23T16:47:11","guid":{"rendered":"\/forum\/forums\/topic\/volume-fraction-problem-in-fluent\/"},"modified":"2024-01-24T17:19:30","modified_gmt":"2024-01-24T17:19:30","slug":"volume-fraction-problem-in-fluent","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/volume-fraction-problem-in-fluent\/","title":{"rendered":"Volume fraction problem in fluent"},"content":{"rendered":"
Hi all.<\/div>\n
Previously, I calculated a centrifugal pump with water. Everything was perfect.<\/div>\n
Now I carry out the calculation on the mixture.<\/div>\n
The mixture is water + 5 percent methane.<\/div>\n
I use inlet flow and outlet pressure. I determined the outlet pressure from calculations on water.<\/div>\n
OK. Water consumption is 3.511 kg\/s, gas consumption is 0.00013 kg\/s.<\/div>\n
The outlet pressure is 2 atm. Backflow volume fraction = 0.<\/div>\n
I encountered these problems:<\/div>\n
1. After 700 iterations, continuity begins to increase, while the input pressure decreases greatly and an error occurs.<\/div>\n
<\/div>\n
2. I watch the convergence graphs. After 700 iterations, all the graphs reach a flat line, but I see that the methane output flow rate is 0. Although the methane input flow rate shows 0.0001:<\/div>\n
<\/div>\n
<\/div>\n
<\/div>\n
<\/div>\n
 <\/div>\n
After 700 iterations, I looked at the cross-section of volume fraction and pressure, they look like this:<\/div>\n
<\/div>\n
<\/div>\n
 <\/div>\n
It seems that the gas fraction is stuck in the supply pipe and does not go further. Why?<\/div>\n
 <\/div>\n
I use the coupled method and second orders.<\/div>\n
I tried to solve the problem like this:<\/div>\n
– used third orders<\/div>\n
– turned on high relaxation and indicated all 0.25<\/div>\n
– I did a strong relaxation to 0.25<\/div>\n
<\/div>\n
 <\/div>\n
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 <\/div>\n
I ask for your help. Thank you.<\/strong><\/div>\n","protected":false},"template":"","class_list":["post-346215","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["257647","852","199"],"_bbp_author_ip":["23.206.193.146"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["495"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_notification_enabled":["442606","442606","442606","442606"],"_bbp_topic_id":["346215"],"_bbp_forum_id":["27792"],"_bbp_engagement":["199","852","257647"],"_bbp_voice_count":["3"],"_bbp_reply_count":["5"],"_bbp_last_reply_id":["346412"],"_bbp_last_active_id":["346412"],"_bbp_last_active_time":["2024-01-24 17:18:40"]},"test":"javat33489gmail-com"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/346215","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\/346215\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=346215"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}