[cli21]

Hi,

I am a new user of ansys. I was stuck at a problem which I've no idea what I did wrong.

The problem is described detailed as below.

First, I use solidwork to build a simple 3D beam structure.

Structure thickness is 25um.
When i build the structure using solidworks, I choose unit system MMGS(milimeter, gram, second), and saved the structure as parasolid(.x_t) file.

Then I imported the structure into Ansys 15.0(also tried Ansys 16.0), did the following steps:
1. define element ( solid 20node 186)
2. Import material properties. (material is silicon)
3. mesh(using smart mesh, set the level to 1)
4. Set analysis type(static)
5. define boundary conditions(set the four supporting beam ends fixed in all DOF)
6. add a force to the central shuttle, negative Z direction, value 10uN.

7. solve LS

The result I got is like this(contour plot-nodal solution-Z component of displacement)


The result is contradictory to common sense, how could the upper supporting beams bent toward the opposite direction of the force? How could the lower part of shuttle has a negative displacement while beam a positive direction pulling force?

I wish somebody could point out my mistakes.

Thanks in advance.