{"id":354453,"date":"2024-02-29T06:53:07","date_gmt":"2024-02-29T06:53:07","guid":{"rendered":"\/forum\/forums\/topic\/problems-of-dpm-concentration-udf\/"},"modified":"2024-02-29T06:53:07","modified_gmt":"2024-02-29T06:53:07","slug":"problems-of-dpm-concentration-udf","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/problems-of-dpm-concentration-udf\/","title":{"rendered":"Problems of  DPM concentration UDF"},"content":{"rendered":"<p>Hello everyone,<\/p>\n<p>I try to employ a UDF to calculate the DPM concentration, I add one UDMI before the simulation, and initialize particles uniformly distributed in a room (volume injection).&nbsp; I set up an air conditioner and air purifier to dilute the particles. After the simulation is complete, I use Report &#8211; Volume integral &#8211; Volume average to compute the concentration (variable: User-Defined Memory ). I&#8217;m not sure if the way I compute the concentration is correct or not because the computed value is gradually increase with the time instead of decreasing (should be decreasing). Can someone give me some guidance? The following picture is my UDF code.&nbsp;<\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2024\/02\/29-02-2024-1709189214-mceclip0.png\"><\/p>\n","protected":false},"template":"","class_list":["post-354453","topic","type-topic","status-closed","hentry","topic-tag-dpm","topic-tag-dpm-concentration","topic-tag-dpm-udfs"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["337173","852"],"_bbp_author_ip":["23.218.248.146"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["517"],"_bbp_topic_status":["unanswered"],"_bbp_topic_id":["354453"],"_bbp_forum_id":["27792"],"_bbp_engagement":["852","337173"],"_bbp_voice_count":["2"],"_bbp_reply_count":["11"],"_bbp_last_reply_id":["358115"],"_bbp_last_active_id":["358115"],"_bbp_last_active_time":["2024-03-20 11:36:27"]},"test":"bill430325gmail-com"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/354453","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\/354453\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=354453"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}