{"id":171100,"date":"2023-06-05T07:05:41","date_gmt":"2023-06-05T07:05:41","guid":{"rendered":"\/knowledge\/forums\/topic\/divide-by-zero-error-occurs-when-calculating-the-swirl-number-swirl-tangential-velocity-axial-velocity\/"},"modified":"2023-07-31T12:30:03","modified_gmt":"2023-07-31T12:30:03","slug":"divide-by-zero-error-occurs-when-calculating-the-swirl-number-swirl-tangential-velocity-axial-velocity","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/divide-by-zero-error-occurs-when-calculating-the-swirl-number-swirl-tangential-velocity-axial-velocity\/","title":{"rendered":"Divide by zero error occurs when calculating the swirl number  Swirl = tangential velocity \/ axial velocity"},"content":{"rendered":"<p>The problem is that the axial velocity will be zero somewhere in the domain, often along the axis where the flow reverses in the presence of a precessing vortex core.   The solution is to instead calculate:  Swirl = tangential velocity \/ (axial velocity  + 0.000001 [ms^-1]<\/p>\n","protected":false},"template":"","class_list":["post-171100","topic","type-topic","status-publish","hentry","topic-tag-4422","topic-tag-cfd-post","topic-tag-fluid-dynamics","topic-tag-general"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 4.9.10 - aioseo.com -->\n\t<meta name=\"description\" content=\"The problem is that the axial velocity will be zero somewhere in the domain, often along the axis where the flow reverses in the presence of a precessing vortex core. The solution is to instead calculate: Swirl = tangential velocity \/ (axial velocity + 0.000001 [ms^-1]\" \/>\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<link rel=\"canonical\" href=\"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/divide-by-zero-error-occurs-when-calculating-the-swirl-number-swirl-tangential-velocity-axial-velocity\/\" \/>\n\t<meta name=\"generator\" content=\"All in One SEO (AIOSEO) 4.9.10\" \/>\n\t\t<meta property=\"og:locale\" content=\"en_US\" \/>\n\t\t<meta property=\"og:site_name\" content=\"Ansys Knowledge | Ansys Innovation Space\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"Divide by zero error occurs when calculating the swirl number Swirl = tangential velocity \/ axial velocity | Ansys Knowledge\" \/>\n\t\t<meta property=\"og:description\" content=\"The problem is that the axial velocity will be zero somewhere in the domain, often along the axis where the flow reverses in the presence of a precessing vortex core. 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