{"id":397522,"date":"2024-12-15T09:56:00","date_gmt":"2024-12-15T09:56:00","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/issue-with-symmetry-conditions-in-wet-running-multi-disk-clutch-simulation\/"},"modified":"2024-12-15T09:56:00","modified_gmt":"2024-12-15T09:56:00","slug":"issue-with-symmetry-conditions-in-wet-running-multi-disk-clutch-simulation","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/issue-with-symmetry-conditions-in-wet-running-multi-disk-clutch-simulation\/","title":{"rendered":"Issue with Symmetry Conditions in Wet-Running Multi-Disk Clutch Simulation"},"content":{"rendered":"<p>&lt;p&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;Hello Dears,&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;I am simulating the oil supply of a&nbsp;<strong>wet-running multi-disk clutch<\/strong> in ANSYS Fluent. The model is divided into two domains: the stator (outer disks that do not rotate) and the rotor (inner disks that rotate). The rotation axis is aligned with the X-axis. I have defined symmetry conditions for the model and performed the simulation.&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;I expected the total pressure to increase in the radial direction due to centrifugal force. However, the results show the following: The velocity vectors are directed tangentially. The fluid flows into the lower symmetry plane and exits through the upper symmetry plane (flow in the tangential direction), which is as expected. However, the static pressure does not increase radially but rather in the tangential direction. This could be causing fluid buildup behind the upper symmetry plane, where the fluid should exit. The total pressure distribution resembles the static pressure pattern. However, the dynamic pressure in the rotating domain seems to be directed radially and increases in the radial direction.&lt;br&gt;<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/12\/15-12-2024-1734255723-dynamic-p-rotor.jpg\" alt=\"\" width=\"351\" height=\"329\" \/>&lt;br&gt;<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/12\/15-12-2024-1734255802-static-p-rotor.jpg\" alt=\"\" width=\"349\" height=\"343\" \/>&lt;br&gt;&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/12\/15-12-2024-1734255878-total-pressure.jpg\" alt=\"\" width=\"348\" height=\"214\" \/>&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/12\/15-12-2024-1734255985-Velocity-vector-symmetry.jpg\" alt=\"\" width=\"345\" height=\"201\" \/>&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;Interestingly, when I simulate the entire model (without symmetry conditions), the pressure contours match my expectations.&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/12\/15-12-2024-1734256074-p-vollkreis.jpg\" alt=\"\" width=\"324\" height=\"200\" \/>&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<strong>Additional Information<\/strong>:&lt;\/span&gt;&lt;\/p&gt;<\/p>\n<ul>&lt;li style=&#8221;font-size: 12pt;&#8221;&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;Gravity is turned off in the simulation.&lt;\/span&gt;<\/li>\n<p>&lt;li style=&#8221;font-size: 12pt;&#8221;&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;The simulation is a <strong>steady-state<\/strong> simulation with <strong>frame motion<\/strong>.&lt;\/span&gt;<\/li>\n<p>&lt;li style=&#8221;font-size: 12pt;&#8221;&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;Inlet type: <strong>Mass Flow Rate<\/strong>&lt;\/span&gt;<\/li>\n<p>&lt;li style=&#8221;font-size: 12pt;&#8221;&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;Outlet type: <strong>Pressure<\/strong>&lt;\/span&gt;<\/li>\n<\/ul>\n<p>&lt;p&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;<strong>Question<\/strong>: Why are the symmetry conditions being ignored in this case?&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;&lt;span style=&#8221;font-size: 12pt;&#8221;&gt;Best regards&lt;\/span&gt;&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-397522","topic","type-topic","status-publish","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_forum_id":["27792"],"_bbp_topic_id":["397522"],"_bbp_subscription":["492731","199"],"_bbp_author_ip":["90.153.14.251"],"_bbp_last_reply_id":["397726"],"_bbp_last_active_id":["397726"],"_bbp_last_active_time":["2024-12-17 10:08:29"],"_bbp_reply_count":["5"],"_bbp_reply_count_hidden":["0"],"_bbp_voice_count":["2"],"_bbp_engagement":["492731","199"],"_btv_view_count":["225"],"_bbp_topic_status":["unanswered"]},"test":"saeideh-kermani-afaranireintjes-gears-de"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/397522","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\/397522\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=397522"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}