{"id":283775,"date":"2023-05-13T11:41:25","date_gmt":"2023-05-13T11:41:25","guid":{"rendered":"\/forum\/forums\/topic\/vortex-induced-vibration-fsi\/"},"modified":"2023-05-13T11:41:25","modified_gmt":"2023-05-13T11:41:25","slug":"vortex-induced-vibration-fsi","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/vortex-induced-vibration-fsi\/","title":{"rendered":"vortex induced vibration FSI"},"content":{"rendered":"

hello, 
i’m trying to simulate the vortex induced vibration through fluid structure interaction, using Fluent and Transient mechanical,
the vibrating object is an Aluminum cylinder(32 mm diameter & 118 mm hight) connected to a thin Aluminum plate (200×25×0.5 mm) within a circular wind tunnel (400mm diameter), where air is flowing with a speed of 2 m\/s.
1. the simulation gone great and the object is vibrating correctly, where both the cylinder and the plate are imported to mechanical APDL as one part made of Aluminum,
2. but when i tried to change the material of the cylinder to another material (foam), and the object is imported to APDL as two boddies connected by BONDED connection, the body did not vibrate at all, 
3. I suspect the Foam material defenition, so I ran the simulation as the cylinder is made of Aluminum again, but as a different part from the plate, but they are connected as BONDED, and the results were different from the 1st simulation, where the plate and the cylinder just shifted to one side and did not oscillate,
So I still think that the problem is in the Bonded Connection between the plate and the cylinder, but it seems to be correctly defined since the 3rd simulation did run and the object moved, but i don’t know why it is different from the 1st simulation where both have the same boundary conditions and materials, 
can you please suggest any modifications or using another connection type? though i think the bonded connection is the logical choice, 
thanks in advance.\"\"\"\"\"\"<\/p>\n","protected":false},"template":"","class_list":["post-283775","topic","type-topic","status-closed","hentry","topic-tag-2-way-coupled-fsi","topic-tag-2-way-fsi","topic-tag-fluent","topic-tag-fsi-2-way-1","topic-tag-transient-structural"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t