Topology optimization leads to zero geometry

Sakarias Johansson
Sakarias Johansson New Altair Community Member
edited October 2022 in Community Q&A

Hi!

I have tried running a simple topology optimization on this simple part.

image

The grey parts have support and a load in the middle. The grey parts are a material that is uncompressed (ie very high elasticity and strength) and the part in aluminum. When i then run the optimization it turns out like this.

image

It doesn't matter what mass i choose the result stays the same.

What am i doing wrong?

Answers

  • Adriano A. Koga
    Adriano A. Koga
    Altair Employee
    edited October 2022

    hi,

     

    what are the optimization options that you are using?

    Minimize Mass? Maximize Stiffness?

    Are you using a constraints such as factor of safety? or volume fraction?

    What is your load magnitude?

    Did you run the model before optimization? What was the maximum stress and displacement before optimization?

    Are you sure the material is correct? the designable part is using Aluminum? or is it also with the very high stiffness material?

  • Sakarias Johansson
    Sakarias Johansson New Altair Community Member
    edited October 2022

    hi,

     

    what are the optimization options that you are using?

    Minimize Mass? Maximize Stiffness?

    Are you using a constraints such as factor of safety? or volume fraction?

    What is your load magnitude?

    Did you run the model before optimization? What was the maximum stress and displacement before optimization?

    Are you sure the material is correct? the designable part is using Aluminum? or is it also with the very high stiffness material?

    Hi!

     

    I've used both minimize mass and maximize stiffnes it doesn't seem to mater. I tired maximize stiffnes and choose low mass like 10% to like 95% and it doesn't make a difference. For minimize mass i tried a plethora of safety factors also. The load is around 10kN (maybe to high?) but that doesn't seem to make a difference ,when i change it, either.

    I don't have the model right now but the displacment was minimal. Yes the designed part was the material aluminum 7075-t6.

    I've yet to figure out the problem :(

  • PaulAltair
    PaulAltair
    Altair Employee
    edited October 2022

    Hi!

     

    I've used both minimize mass and maximize stiffnes it doesn't seem to mater. I tired maximize stiffnes and choose low mass like 10% to like 95% and it doesn't make a difference. For minimize mass i tried a plethora of safety factors also. The load is around 10kN (maybe to high?) but that doesn't seem to make a difference ,when i change it, either.

    I don't have the model right now but the displacment was minimal. Yes the designed part was the material aluminum 7075-t6.

    I've yet to figure out the problem :(

    Only comment from me is that the load on the outside of your grey part is redundant since that face is fixed?

    I made a rough replica of your model and it works fine for me (I didn't include a load on the grey outer part)

    If you can find/share your model it would be interesting to see what the issue is for you

    image