{"id":165954,"date":"2023-03-17T13:10:41","date_gmt":"2023-03-17T13:10:41","guid":{"rendered":"\/knowledge\/forums\/topic\/how-to-write-data-to-a-text-file-from-an-ansys-fluent-udf-that-is-only-executed-on-node-processes\/"},"modified":"2023-07-31T12:27:03","modified_gmt":"2023-07-31T12:27:03","slug":"how-to-write-data-to-a-text-file-from-an-ansys-fluent-udf-that-is-only-executed-on-node-processes","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/how-to-write-data-to-a-text-file-from-an-ansys-fluent-udf-that-is-only-executed-on-node-processes\/","title":{"rendered":"How to write data to a text file from an ANSYS Fluent UDF that is only executed on node processes?"},"content":{"rendered":"<p>When writing data to a file, you usually try doing this from the host process to avoid file access conflicts. Although many DEFINE macros are executed on host and node, some might only be executed on node processes. In this case, it is best to write data only from compute node 0. The attached document provides an example UDF that writes the position for a prescribed motion to a file. File is open from compute node 0 in a DEFINE_CG_MOTION macro.<\/p>\n<p>Attachments:<br \/>\n1. <a href=https:\/\/ansys13.ansys.com\/KnowledgeArticles\/Phase-1\/2055026\/2055026.pdf>2055026.pdf<\/a><br \/>\n2. <a href= https:\/\/ansys13.ansys.com\/KnowledgeArticles\/Phase-1\/2055026\/2055026.zip>2055026.zip<\/a><\/p>\n","protected":false},"template":"","class_list":["post-165954","topic","type-topic","status-publish","hentry","topic-tag-19-1","topic-tag-fluent","topic-tag-fluid-dynamics","topic-tag-general","topic-tag-general-fluent"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 4.9.10 - aioseo.com -->\n\t<meta name=\"description\" content=\"When writing data to a file, you usually try doing this from the host process to avoid file access conflicts. Although many DEFINE macros are executed on host and node, some might only be executed on node processes. In this case, it is best to write data only from compute node 0. The attached document\" \/>\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<link rel=\"canonical\" href=\"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/how-to-write-data-to-a-text-file-from-an-ansys-fluent-udf-that-is-only-executed-on-node-processes\/\" \/>\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=\"How to write data to a text file from an ANSYS Fluent UDF that is only executed on node processes? | Ansys Knowledge\" \/>\n\t\t<meta property=\"og:description\" content=\"When writing data to a file, you usually try doing this from the host process to avoid file access conflicts. Although many DEFINE macros are executed on host and node, some might only be executed on node processes. In this case, it is best to write data only from compute node 0. The attached document\" \/>\n\t\t<meta property=\"og:url\" content=\"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/how-to-write-data-to-a-text-file-from-an-ansys-fluent-udf-that-is-only-executed-on-node-processes\/\" \/>\n\t\t<meta property=\"article:published_time\" content=\"2023-03-17T13:10:41+00:00\" \/>\n\t\t<meta property=\"article:modified_time\" content=\"2023-07-31T12:27:03+00:00\" \/>\n\t\t<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n\t\t<meta name=\"twitter:title\" content=\"How to write data to a text file from an ANSYS Fluent UDF that is only executed on node processes? | Ansys Knowledge\" \/>\n\t\t<meta name=\"twitter:description\" content=\"When writing data to a file, you usually try doing this from the host process to avoid file access conflicts. Although many DEFINE macros are executed on host and node, some might only be executed on node processes. In this case, it is best to write data only from compute node 0. 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