{"id":388706,"date":"2024-10-09T07:22:17","date_gmt":"2024-10-09T07:22:17","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/savonius-2d-simulation-cp-increasing-after-stall-point\/"},"modified":"2024-10-09T07:22:17","modified_gmt":"2024-10-09T07:22:17","slug":"savonius-2d-simulation-cp-increasing-after-stall-point","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/savonius-2d-simulation-cp-increasing-after-stall-point\/","title":{"rendered":"Savonius 2D simulation, Cp increasing after stall point"},"content":{"rendered":"<p>&lt;p&gt;Hi everyone,&lt;\/p&gt;&lt;p&gt;I am currently working on Savonius hydro turbine in 2D. During my validation I noticed that up to the stall point, the trend is following, but after the stall point the Cp is still increasing. I have tried different methods like changing the scheme, turbulence model, gradients and validation paper also. Still I persist the same issue.&lt;\/p&gt;&lt;p&gt;&nbsp;My wall y+ is also &lt;1. It can be seen from the images that at TSR 0.6 where it is matching with experiment, my streamlines are connecting outside and inside the MRF, while at after stall point it is not.&lt;\/p&gt;&lt;p&gt;&nbsp;(ignore fluid air, I manually input the values of water and did not change the name). My my mesh count is closer to 0.37 million which can be seen in literature also for 2D case. The boundary conditions are symmetry sides and pressure outlet with blades as wall. (negative omega as it is rotating in Clockwise direction).&nbsp;&lt;\/p&gt;&lt;p&gt;Can someone please help me, I am stuck in this for te past 3 months.&lt;\/p&gt;&lt;p&gt;<img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/10\/09-10-2024-1728458098-velocity TSR 0.6.jpg\" alt=\"Velocity streamline at TSR=0.6\" \/><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/10\/09-10-2024-1728457743-validation graph.JPG\" alt=\"Validation stall point\" width=\"356\" height=\"211\" \/><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/10\/09-10-2024-1728458162-courant number.JPG\" alt=\"Courant number at TSR=1.1\" width=\"384\" height=\"313\" \/><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/10\/09-10-2024-1728458055-blade_inflation.JPG\" alt=\"Blade inflation layer\" width=\"622\" height=\"346\" \/><img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/10\/09-10-2024-1728458124-velocity TSR 1.1.jpg\" alt=\"Velocity streamlines at TSR=1.1\" \/><img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/10\/09-10-2024-1728458478-mceclip0.png\" alt=\"Courant number at TSR=0.6\" \/>&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-388706","topic","type-topic","status-publish","hentry","topic-tag-cfd","topic-tag-fluent","topic-tag-sliding-mesh","topic-tag-turbine","topic-tag-turbine-rotation-2","topic-tag-wind-turbine","topic-tag-wind-turbine-cfd"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_author_ip":["103.158.43.22"],"_btv_view_count":["450"],"_bbp_topic_status":["unanswered"],"_bbp_subscription":["199","423155"],"_bbp_topic_id":["388706"],"_bbp_forum_id":["27792"],"_bbp_engagement":["199","423155"],"_bbp_voice_count":["2"],"_bbp_reply_count":["23"],"_bbp_last_reply_id":["389253"],"_bbp_last_active_id":["389253"],"_bbp_last_active_time":["2024-10-11 12:14:21"]},"test":"oe23s006smail-iitm-ac-in"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/388706","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\/388706\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=388706"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}