{"id":426271,"date":"2025-03-19T23:56:29","date_gmt":"2025-03-19T23:56:29","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/momentum-source-not-changing-flow-rate-in-a-closed-loop-circuit\/"},"modified":"2025-03-19T23:56:29","modified_gmt":"2025-03-19T23:56:29","slug":"momentum-source-not-changing-flow-rate-in-a-closed-loop-circuit","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/momentum-source-not-changing-flow-rate-in-a-closed-loop-circuit\/","title":{"rendered":"Momentum Source Not Changing Flow Rate in a Closed-Loop Circuit"},"content":{"rendered":"
<p data-start=”116″ data-end=”380″><\/p><p data-start=”116″ data-end=”380″>I am working on a <strong data-start=”134″ data-end=”163″>closed-loop fluid circuit<\/strong> in ANSYS Fluent and using a <strong data-start=”192″ data-end=”211″>momentum source<\/strong> to simulate a pump. However, despite applying the source term, the <strong data-start=”279″ data-end=”310″>flow rate remains unchanged<\/strong>, and I don’t see the expected increase in velocity within the loop.<\/p><p data-start=”116″ data-end=”380″> <\/p><p data-start=”382″ data-end=”416″>Here’s what I have tried so far:<\/p><ul data-start=”417″ data-end=”820″><li data-start=”417″ data-end=”490″>Applied the momentum source in the pump region in the image.<\/li>\n
<li data-start=”491″ data-end=”588″>Increased the source term magnitude significantly, but no noticeable effect on the flow rate.<\/li>\n
<li data-start=”589″ data-end=”730″>Checked boundary conditions—since this is a <strong data-start=”635″ data-end=”657″>closed-loop system<\/strong>, there are no inlets or outlets, just walls. <\/li>\n<\/ul>\n
<p data-start=”822″ data-end=”994″>I was expecting the momentum source to drive the flow, similar to how a pump would, but it doesn’t seem to be working. I have attached an image of my setup for reference.<\/p><p data-start=”996″ data-end=”1103″>Has anyone encountered this issue before? Are there additional settings or considerations I should check?<\/p><p data-start=”1105″ data-end=”1149″>Any insights would be greatly appreciated!<\/p><p data-start=”1151″ data-end=”1169″ data-is-last-node=”” data-is-only-node=””>Thanks in advance.<\/p><\/p>\n","protected":false},"template":"","class_list":["post-426271","topic","type-topic","status-publish","hentry"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t
![](\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2025\/03\/19-03-2025-1742428548-mceclip0.png\")
<\/p><p data-start=”116″ data-end=”380″>I am![](\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2025\/03\/19-03-2025-1742428566-mceclip1.png\")
working on a <strong data-start=”134″ data-end=”163″>closed-loop fluid circuit<\/strong> in ANSYS Fluent and using a <strong data-start=”192″ data-end=”211″>momentum source<\/strong> to simulate a pump. However, despite applying the source term, the <strong data-start=”279″ data-end=”310″>flow rate remains unchanged<\/strong>, and I don’t see the expected increase in velocity within the loop.<\/p><p data-start=”116″ data-end=”380″> <\/p><p data-start=”382″ data-end=”416″>Here’s what I have tried so far:<\/p><ul data-start=”417″ data-end=”820″><li data-start=”417″ data-end=”490″>Applied the momentum source in the pump region in the image.<\/li>\n