Hello Ying,

I just created a test model with 1 rigid element and the motion makes sense. The units are ton, mm, s, N, MPa. At time 0, the velocity of the 1 element rigid cube is 1000 mm/s using an *INITIAL_VELOCITY_RIGID. Then, the velocity vs displacement curve is as follows:

Note that it is good practice to extend the curve beyond the point we want to go.

In this case, the relationship between velocity and displacement is linear and as follows:

v = -20*d + 1000

When I look at the results, the velocity at each displacement makes sense. For example when the displacement in X is 16.4706 mm, the velocity in LSPP is 670.586 mm/s which is close to the value calculated with the equation above (670.588 mm/s). I checked many displacement and velocities for the rigid cube and then always match.

I ran on Windows with R12.0.0 MPP double precision with Intel MPI.

I will post the model in the next post. Let me know if it works on your side or not.

Reno.