


{"id":293028,"date":"2023-07-14T02:30:22","date_gmt":"2023-07-14T02:30:22","guid":{"rendered":"\/forum\/forums\/topic\/piston-motion-problem-dynamic-mesh-and-fluid-zone-motion\/"},"modified":"2023-07-16T09:04:01","modified_gmt":"2023-07-16T09:04:01","slug":"piston-motion-problem-dynamic-mesh-and-fluid-zone-motion","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/piston-motion-problem-dynamic-mesh-and-fluid-zone-motion\/","title":{"rendered":"Piston motion problem: Dynamic mesh and fluid zone motion"},"content":{"rendered":"<p class=\"MsoNormal\" style=\"text-align: justify\"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <\/span>Hello,<\/p>\n<p class=\"MsoNormal\" style=\"text-align: justify\"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <\/span>I want to simulate the motion of a piston which contains an oil film(about 50 um thick) at the bottom of it, all fluid parts are shown in <strong>Figure 1<\/strong>, each fluid zone is connected by interface.<\/p>\n<p class=\"MsoNormal\" style=\"text-align: justify\"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <\/span>The moving zones consist of 4 parts, shown in <strong>Figure 2<\/strong>:<\/p>\n<p class=\"MsoNormal\" style=\"text-align: justify\">(1) the bottom face of piston cylinder, which is labelled as moving face;<\/p>\n<p class=\"MsoNormal\" style=\"text-align: justify\">(2) fluid zone 2;<\/p>\n<p class=\"MsoNormal\" style=\"text-align: justify\">(3) fluid zone 3;<\/p>\n<p class=\"MsoNormal\" style=\"text-align: justify\">(4) fluid zone 4;<\/p>\n<p class=\"MsoNormal\" style=\"text-align: justify\"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <\/span>During the motion, piston cylinder is in the suction stage, i.e. the moving parts move along the axis-x with the same velocity V, shown as <strong>Figure 3<\/strong>.<\/p>\n<p class=\"MsoNormal\" style=\"text-align: justify\"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <\/span>I know this motion involves with dynamic mesh and UDF, besides, if without the fluid zone 2, 3, 4, I can use UDF &ldquo;CG_MOTION&rdquo; to realize the motion of piston, but once the three other fluid zones are added, I have no idea how to deal with.<\/p>\n<p class=\"MsoNormal\" style=\"text-align: justify\"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <\/span>Any advice would be appreciated.<\/p>\n<p class=\"MsoNormal\" style=\"text-align: justify\">Regards,<\/p>\n<p class=\"MsoNormal\" style=\"text-align: justify\"><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/07\/14-07-2023-1689299476-mceclip0.png\"><\/p>\n<p class=\"MsoNormal\" style=\"text-align: left\" align=\"center\"><strong>Figure 1<\/strong><\/p>\n<p class=\"MsoNormal\" style=\"text-align: justify\"><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/07\/14-07-2023-1689299665-mceclip1.png\"><\/p>\n<p class=\"MsoNormal\" style=\"text-align: left\" align=\"center\"><strong>Figure 2<\/strong><\/p>\n<p class=\"MsoNormal\" style=\"text-align: justify\"><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/07\/14-07-2023-1689299680-mceclip2.png\"><\/p>\n<p class=\"MsoNormal\" style=\"text-align: left\" align=\"center\"><strong>Figure 3<\/strong><\/p>\n<p class=\"MsoNormal\" style=\"text-align: justify\">&nbsp;<\/p>\n","protected":false},"template":"","class_list":["post-293028","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["184661","13659"],"_bbp_author_ip":["23.206.193.156"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["261"],"_bbp_status":["publish"],"_bbp_topic_status":["unanswered"],"_bbp_topic_id":["293028"],"_bbp_forum_id":["27792"],"_bbp_engagement":["13659","184661"],"_bbp_voice_count":["2"],"_bbp_reply_count":["2"],"_bbp_last_reply_id":["293248"],"_bbp_last_active_id":["293248"],"_bbp_last_active_time":["2023-07-16 09:03:10"]},"test":"excited"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/293028","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\/293028\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=293028"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}