{"id":279232,"date":"2023-04-13T09:39:27","date_gmt":"2023-04-13T09:39:27","guid":{"rendered":"\/forum\/forums\/topic\/how-to-understand-y-axis-under-cylindrical-coordinate-system\/"},"modified":"2023-04-13T09:43:17","modified_gmt":"2023-04-13T09:43:17","slug":"how-to-understand-y-axis-under-cylindrical-coordinate-system","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/how-to-understand-y-axis-under-cylindrical-coordinate-system\/","title":{"rendered":"How to understand y axis under cylindrical coordinate system \uff1f"},"content":{"rendered":"

I know that in ANSYS, if I select the current coordinate system as the cylindrical coordinate system (csys,1), then x represents r, y represents r*Δθ, which is the distance along the circumference, and z is consistent with the Cartesian coordinate system. However, when I process my modal shape results in the post-processor (\/post1), I still encounter difficulties in understanding.<\/p>\n

I tried to perform a modal analysis on a compressor’s bladed disk and extract its mode shapes. The modal analysis is based on a single-sector model with cyclic symmetry settings.<\/p>\n

As shown in the figure below, when I predefine the global coordinate system as the global cylindrical coordinate system (csys,1) and specify the result coordinate system in \/post1 to also use the solution coordinate system (rsys,solu), I extract the modal shape data of a single sector. The value of y (which is rθ) is very large. When I divide y by x to obtain the θ value in the cylindrical coordinate system, it still exceeds the range of (-π,π), which confuses me.<\/p>\n

When I extract the mode shapes of the entire disk, the value of y is still very large, indicating that the error is not caused by extracting the mode shapes of a single sector.<\/p>\n

I would like to know what such a large y value represents, whether the θ it reflects is truly usable, or if I need to do some processing to make it usable. (Please note that I used the PRNSOL command to display the mode shapes, and GPT-4 told me that the mode shapes extracted using this command have not been scaled, i.e., they are the original mode shape data.)\"\"<\/p>\n","protected":false},"template":"","class_list":["post-279232","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["209412","23687","170445"],"_bbp_author_ip":["23.220.96.180"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["7470"],"_bbp_likes_count":["0"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["279232"],"_bbp_forum_id":["27791"],"_bbp_engagement":["23687","170445","209412"],"_bbp_voice_count":["3"],"_bbp_reply_count":["4"],"_bbp_last_reply_id":["279518"],"_bbp_last_active_id":["279518"],"_bbp_last_active_time":["2023-04-14 13:35:06"]},"test":"biao-zhoupolito-it"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/279232","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\/279232\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=279232"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}