{"id":382818,"date":"2024-09-16T20:09:31","date_gmt":"2024-09-16T20:09:31","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/unexpected-force-relative-to-distance-curve-repelling-magnets\/"},"modified":"2024-09-16T20:11:40","modified_gmt":"2024-09-16T20:11:40","slug":"unexpected-force-relative-to-distance-curve-repelling-magnets","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/unexpected-force-relative-to-distance-curve-repelling-magnets\/","title":{"rendered":"Unexpected force relative to distance curve – Repelling magnets"},"content":{"rendered":"

<p><p><p>Hi all,<\/p><p>I have created a model consisting of an outer ring of twelfth 35*20mm magnets in a circle of diameter 200, with a disc magnet of 5*60mm at a height of 70 mm. As shown below:<br><br><\/p><p><\/p><p>(the box next to it is vacuum, and just used to specify a local coordinate system).<\/p><p>I then set up a parametric simulation to increase the disc’s height from 40 to 90mm, expecting a decreasing force. But for some reason, the force seems to jump around a lot.<br><br><\/p><p> <\/p><p> <\/p><p>The same type of effect seems to occur for X, whereas I would expect that it essentially stay 0 since the disc magnet is exactly in the middle of the ring of magnets (it only moves in the Z direction):<br><br><\/p><p>I’ve used the default analysis setup, with the initial mesh settings resolution set to 5. I also made sure that the magnetization direction is upwards\/in the Z direction for all magnets.<\/p><p>When I look at the B field plot on some planes, it does look normal to me:<\/p><p><\/p><p>I’ve used the default NdFe35 material for the disc magnet, and a altered version to get a grade 45 magnet specified this for the ring of magnets:<\/p><p><\/p><p> <\/p><p>This is my first time using this software, so I’m kind of stuck now as I have no clue what might be causing this. Could somebody perhaps point me in the right direction?<br><br><br><\/p><\/p><\/p><\/p>\n","protected":false},"template":"","class_list":["post-382818","topic","type-topic","status-publish","hentry","topic-tag-magnet"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["456705","284053"],"_bbp_author_ip":["217.123.103.98"],"_btv_view_count":["123"],"_bbp_topic_status":["unanswered"],"_edit_last":["456705"],"_bbp_revision_log":["a:2:{i:382819;a:2:{s:6:\"author\";i:456705;s:6:\"reason\";s:0:\"\";}i:382820;a:2:{s:6:\"author\";i:456705;s:6:\"reason\";s:0:\"\";}}"],"_edit_lock":["1726517509:456705"],"_bbp_topic_id":["382818"],"_bbp_forum_id":["27793"],"_bbp_engagement":["284053","456705"],"_bbp_voice_count":["2"],"_bbp_reply_count":["1"],"_bbp_last_reply_id":["382879"],"_bbp_last_active_id":["382879"],"_bbp_last_active_time":["2024-09-17 14:25:28"]},"test":"h-smeitinkgmail-com"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/382818","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":2,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/382818\/revisions"}],"predecessor-version":[{"id":382820,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/382818\/revisions\/382820"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=382818"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}