{"id":373873,"date":"2024-07-28T09:31:52","date_gmt":"2024-07-28T09:31:52","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/2d-savonius-rotor-simulation-validation-problems\/"},"modified":"2024-07-28T09:31:52","modified_gmt":"2024-07-28T09:31:52","slug":"2d-savonius-rotor-simulation-validation-problems","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/2d-savonius-rotor-simulation-validation-problems\/","title":{"rendered":"2D Savonius Rotor simulation Validation problems"},"content":{"rendered":"

Hello,
I’ve been trying to simulate a 2D Savonius rotor and validate the power coefficient data with the laboratory data obtained in the paper I found, however, the ansys simulation underpredicts the experimental data. I constructed the geometry in spaceclaim, using dimensions given in the paper and carried out a mesh refinement study by measuring the torque when the rotor is stationary.<\/p>\n

<\/p>\n

<\/p>\n

<\/p>\n

As well as this, I tried to make sure that the y+ values at the walls of the rotor blades were <1.
<\/p>\n

<\/p>\n

Using the sliding mesh approach I would change the rotational speed of the rotor and measure the torque to obtain the Torque coefficient and finally the Power coefficient to construct a power curve.<\/p>\n

<\/p>\n

<\/p>\n

The following input was used in set-up:
1. Turbulence model: Transition SST (4 eqn)
2. Fluid used: Air (1.225 kg\/m3)
3. Velocity inlet: x-component = 7m\/s, y-component = 0 m\/s
4. Solution method used: SIMPLE with spatial discretization gradient set to least Square cells based, and all other parameters set to second order.
5. Reference values are computed from the inlet.
6. Torque was measured from both blades at the centre of rotation of the rotating domain.
7. Hybrid initialization was used.
8. The time step size was found using the CFL criterion \u2206t≤ \u2206x\/v, where the number of time steps was adjusted at different rotor speeds whilst keeping the time step size constant.<\/p>\n

<\/p>\n

My Ansys data is extremely underpredicting the experimental data. Could anyone please give me some advice as to what might be going wrong? Thank you.<\/p>\n

<\/p>\n","protected":false},"template":"","class_list":["post-373873","topic","type-topic","status-closed","hentry","topic-tag-sliding-mesh"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["397415","13659"],"_bbp_author_ip":["62.228.65.48"]," _bbp_last_reply_id":["0"],"_btv_view_count":["158"]," _bbp_likes_count":["0"],"_bbp_topic_status":["unanswered"],"_bbp_topic_id":["373873"],"_bbp_forum_id":["27792"],"_bbp_engagement":["13659","397415"],"_bbp_voice_count":["2"],"_bbp_reply_count":["4"],"_bbp_last_reply_id":["374053"],"_bbp_last_active_id":["374053"],"_bbp_last_active_time":["2024-07-29 15:30:43"]},"test":"vrwillettsdundee-ac-uk"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/373873","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\/373873\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=373873"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}