Learning Forum

[Alberto]

Dear all,

i'm trying to simulate the 1Degree of freedom dynamics using overset mesh method and 6dof solver with k-w SST model for the fluid.

 

What i'm wondering about is that for the 6dof (complete dynamics) and 2dof (i.e. allowing the object to translate and rotate along vertical z axis) i retrieve in the steady state the expected value of lift force (Fz).

Why when i'm doing the 1dof simulation (i.e. only rotation along z) where i replaced the falling vertical velocity with a ramp function up to the 2dof measured falling speed, i get a lower (15% ) value of Fz ?

This is strange cause my boundary conditions are well posed and the fluid and the solid both converges up to 10^-5 as residuals..

 

Can someone explain me this difference? 

many thanks in advance

[Federico]

You mention in 2DOF your object is translating in the same axis as your rotation. Is this correct?

I assume you are adding the falling velocity to the same flow you had in your 2DOF problem.

Can you show some contours of each solution?