🎉Community Raffle - Win $25

An exclusive raffle opportunity for active members like you! Complete your profile, answer questions and get your first accepted badge to enter the raffle.
Join and Win

Cantilever Beam's displacement can't match the analysis result

User: "Altair Forum User"
Altair Employee
Updated by Altair Forum User

I have do the simple supported beam's analysis

 

and when I calculate the displacement of middle, it will still have 4.8% difference.

 

But my element size is about 10 mm.

 

Why I can't match them.

 

I watch the z-displacement. 

 

I have refine it but it still wrong.

 

image.png.942d02447c2e686ccf7f75165bae3740.png 

image.png.633ad532f5e161f79ef2085b07b1d3ea.png

Unable to find an attachment - read this blog

Find more posts tagged with

Sort by:
1 - 11 of 111
    User: "QuyNguyenDai"
    Altair Community Member
    Updated by QuyNguyenDai

    Try to refine more your mesh. Your current mesh is rather 'coarse' for me.

    User: "Altair Forum User"
    Altair Employee
    OP
    Updated by Altair Forum User

    @Q.Nguyen-Dai 

     

    I have try more mesh like the file Pressure_Modify_Size 2.fem

     

    Because we use other analysis software.

     

    It use less mesh and can approach, so we don't know why OpitStruct can't convergence.

     

    image.png.eaa7bcbdb82fc0f2ed4fc59f214bebc3.png

     

    I see the result is used this setting

     

    image.png.321fcbf2029ecd31746d0e9295573923.png

     

    User: "QuyNguyenDai"
    Altair Community Member
    Updated by QuyNguyenDai

    Your refine  mesh is WRONG! I'll show you later

    User: "Altair Forum User"
    Altair Employee
    OP
    Updated by Altair Forum User

    @Q.Nguyen-Dai Thanks for you.

     

    I think you are talking about the full model refine.

     

    But I have another example like my last reply, it is convergence.

     

    Because if this simple case the element size can't be 10mm or need finer.

     

    In the future, our model must be under this size. I think is not reasonable.

    User: "QuyNguyenDai"
    Altair Community Member
    Updated by QuyNguyenDai

    Within model 'Pressure_Modify Size 2.fem' you have refined at middle of beam, why?

    That's not the good method to refine in order to get better results.

    In your case, the first area you have to refine is at clamp. Because in this area, you have the most important stress gradient.

     

    User: "Altair Forum User"
    Altair Employee
    OP
    Updated by Altair Forum User

    @Q.Nguyen-Dai I think is the boundary I constrain all d.o.f.

     

    I think it should release some d.o.f.

     

    Do you have any other suggestions?

    User: "tinh"
    Altair Community Member
    Updated by tinh

    In your model, force position seems to be incorrect

    you use PLOAD4 on a layer of solid => so force position is at middle of that layer while it should act at one end of the beam

    User: "Altair Forum User"
    Altair Employee
    OP
    Updated by Altair Forum User

    @tinh Thanks to your reply.

     

    So I can't apply on the surface of element.

     

    And how should I apply at the position.

    User: "tinh"
    Altair Community Member
    Updated by tinh

    Distribute it to nodes at the end of beam

    User: "Nachiket Kadu_22143"
    Altair Community Member
    Updated by Nachiket Kadu_22143

    In your model, force position seems to be incorrect

    you use PLOAD4 on a layer of solid => so force position is at middle of that layer while it should act at one end of the beam

    Yes magnitude as well as type of load doesnt match with the hand hand calculation. Also unit system for fea and hand calculation could be differing. Kindly take note of it.

    User: "Altair Forum User"
    Altair Employee
    OP
    Updated by Altair Forum User

    @Nachiket Kadu @tinh

     

    Thanks to your apply!

     

    I have finished this problem.