{"id":382249,"date":"2024-09-11T03:52:01","date_gmt":"2024-09-11T03:52:01","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/define_pr_rate\/"},"modified":"2024-09-11T03:52:01","modified_gmt":"2024-09-11T03:52:01","slug":"define_pr_rate","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/define_pr_rate\/","title":{"rendered":"define_pr_rate"},"content":{"rendered":"<p>&lt;p&gt;I am using the <code>DEFINE_PR_RATE<\/code> UDF to calculate the reaction rate for the reduction of Fe\u2082O\u2083 with H\u2082. My reaction rate equation also depends on the partial pressures of H\u2082 and H\u2082O. In the macro, there is an argument <code>pp<\/code> that contains the gas partial pressures.&lt;\/p&gt;&lt;p&gt;If I use <code>pp[3]<\/code> to represent the partial pressure of H\u2082, after calculating the reaction rate for the first iteration, will Fluent automatically update the partial pressures of these species? Specifically, will it account for the fact that some of the hydrogen has been consumed and water vapor produced, thus altering the partial pressures?&lt;\/p&gt;&lt;p&gt;If the macro does not consider these updated values automatically, do I need to update the gas species fractions and then recalculate the partial pressures? If so, how can I update the gas species fractions and recalculate the partial pressures after each iteration?&lt;\/p&gt;&lt;p&gt;Additionally, do I need to update the temperature in the code as well? If so, how should I go about updating the temperature correctly? thanks in advance&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-382249","topic","type-topic","status-publish","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["73128","199"],"_bbp_author_ip":["129.94.96.29"],"_btv_view_count":["258"],"_bbp_topic_status":["unanswered"],"_bbp_topic_id":["382249"],"_bbp_forum_id":["27792"],"_bbp_engagement":["199","73128"],"_bbp_voice_count":["2"],"_bbp_reply_count":["3"],"_bbp_last_reply_id":["382607"],"_bbp_last_active_id":["382607"],"_bbp_last_active_time":["2024-09-13 12:25:06"]},"test":"z5489721ad-unsw-edu-au"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/382249","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\/382249\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=382249"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}