## General Mechanical

#### Three point bending simulation of sandwich beam structure

• zeddriz
Subscriber

Hello everyone, I hope you all are doing well.

I am reaching out to seek advice to solve some errors encountered in my project. I am currently trying to simulate 3 point bending test of a sandwich composite beam in ANSYS Workbench.  Following are the important details of my ANSYS modeling project:

A sandwich beam (100mm x 12mm x 6mm) with top and bottom skins and a middle core layer. A force acts on the top face of the beam with the help of a loading bar in the center while two rollers placed at 25mm from either end of the beam act as support. A schematic diagram is attached below: (Image 1)

1. Originally, my sandwich beam has dimensions of length = 100mm, width = 12 mm and depth (thickness) = 6mm. I followed some previous posts in this forum on sandwich structure and hence used only 1/4 of the model for analysis. So as shown in Image 1, I have modeled only a quarter of the beam (length = 50mm, width = 6mm and thickness = 6mm). After creating the beam, I have created two planes to divide the beam into three bodies, Top skin and bottom skin of thickness 0.5mm each, and a middle core layer of thickness 5mm. I have assigned Carbon Fiber material properties to top and bottom skin and foam property values to core layer in the middle.  (Image 2)

2. I modeled the beam first, extruded it and then used two planes and slice feature to generate the three bodies mentioned in the previous point.

3. I am trying to simulate bending according to ASTM C393 standard. Typically, I created a line under the lower face which represents the left roller acting on the beam. Then, a loading bar will act on the top face of the beam which divided the structure into 1/4 model. I also created a split-face on the tap for pressure pad to be place on the top face.

4. Now for boundary conditions, I entered a displacement boundary condition on the line created on the bottom face to fix the roller. Boundary condition used was Z=0 and others free. Similarly, on the top face, I applied a force Boundary condition of -25N in the vertical Z direction at the face that divided the beam into symmetry. (Image 3)

However, when I solve the model, I get an error stating that 'A result is invalid with the current output control settings'. I am not sure what incorrect settings I am implementing that is generating this error. I have attached the image below (Image 4)

I tried carefully following the tips and instructions mentioned in these previous posts on bending:

But after following the tips, I am still not getting results. I also tried playing with the boundary conditions, like Z=0 and X=0 for the bottom left roller, but I still get the same error. It would be great if someone could help me in this regard.Thank you.