{"id":249149,"date":"2023-02-08T19:03:22","date_gmt":"2023-02-08T19:03:22","guid":{"rendered":"\/forum\/forums\/topic\/in-six-dof-properties-which-value-of-moment-of-inertia-should-i-enter\/"},"modified":"2023-02-09T09:06:44","modified_gmt":"2023-02-09T09:06:44","slug":"in-six-dof-properties-which-value-of-moment-of-inertia-should-i-enter","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/in-six-dof-properties-which-value-of-moment-of-inertia-should-i-enter\/","title":{"rendered":"In Six DOF properties, which value of moment of inertia should I enter?"},"content":{"rendered":"<p><span style=\"font-size: 12pt\">G&#8217;day,<\/span><\/p>\n<p><span style=\"font-size: 12pt\">I want to make the solid geometry swing as a pendulum (rotating about the x-axis), and the magnitude of its moment of inertia is needed. Then I checked the user guide, and it says:<\/span><\/p>\n<p><span style=\"font-size: 12pt\"><em>&#8220;Note that the inertia tensor components are defined <strong>relative to the Center of Gravity<\/strong> and Rigid Body Orientation settings defined in the Dynamic Mesh Zones Dialog Box (p. 3687).&#8221;<\/em><\/span><\/p>\n<p><span style=\"font-size: 12pt\">I don&#8217;t understand what it means by &#8220;<strong>relative to the Centre of Gravity<\/strong>&#8220;. Does it mean &#8220;parallel axis theorem&#8221;? Does it need the moment of inertia about the axis passing through its centre of mass? Or it needs the moment of inertia about the rotating axis (here indicating the x-axis)?<\/span><\/p>\n<p><span style=\"font-size: 12pt\">Hope someone can help me out, please. Thanks a lot.<\/span><\/p>\n<p><span style=\"font-size: 12pt\"><a class=\"wp-colorbox-image cboxElement\" href=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/02\/08-02-2023-1675882699-Screenshot 2023-02-08 232631.png\"><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/02\/08-02-2023-1675882699-Screenshot 2023-02-08 232631.png\" alt=\"\"><\/a><\/span><\/p>\n","protected":false},"template":"","class_list":["post-249149","topic","type-topic","status-closed","hentry","topic-tag-fluent","topic-tag-moment-of-inertia","topic-tag-six-dof-solver"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["273724","13659","275015"],"_bbp_author_ip":["23.44.170.21"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["2310"],"_edit_lock":["1675932735:204221"],"_bbp_likes_count":["1"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["249149"],"_bbp_forum_id":["27792"],"_bbp_engagement":["13659","273724","275015"],"_bbp_voice_count":["3"],"_bbp_reply_count":["10"],"_bbp_last_reply_id":["279135"],"_bbp_last_active_id":["279135"],"_bbp_last_active_time":["2023-04-12 18:30:53"]},"test":"f24071085gs-ncku-edu-tw"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/249149","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\/249149\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=249149"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}