Can't create Electric Loop Cut

Andoni Garcia
Andoni Garcia Altair Community Member
edited October 2020 in Community Q&A

Hi, 

 

I'm doing some cooling orifices to a solid conductor using 'Modeler Context' and when I use 'Automatic Creation of Cuts' (of Electric Loops), it creates less cuts than the identified ones.

What can I do in this situations? Modifying the geometry would be the only solution?

 

Thanks 

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Answers

  • asoualmi
    asoualmi
    Altair Employee
    edited April 2020

    Hi,

    To create the rest of the cuts, you can use the command create cut (two possibilities to create cut in Flux, automatic/manually) and you need to select the face for each cut you create.

     

    Best regards.

  • Andoni Garcia
    Andoni Garcia Altair Community Member
    edited April 2020

    Hi,

    To create the rest of the cuts, you can use the command create cut (two possibilities to create cut in Flux, automatic/manually) and you need to select the face for each cut you create.

     

    Best regards.

     

    image.png.49e2b2a038713900bc7e23ef06bfb495.png

  • asoualmi
    asoualmi
    Altair Employee
    edited April 2020

    Can you share your project?

     

    Best regards.

  • Andoni Garcia
    Andoni Garcia Altair Community Member
    edited April 2020

    Can you share your project?

     

    Best regards.

     

    Here it is.

     

    Thank you

    Unable to find an attachment - read this blog

  • asoualmi
    asoualmi
    Altair Employee
    edited April 2020

    Hi,

    You ill find attached a PDF file explain how to use the electrical (magnetic) cut in Flux and how much we need.

     

    Some comments about the project that you send me :

    • Infinite box, when you build the infinite box, it is better to use the command “complete infinite box” to build the face and volume. To do it, select the infinite box >> right click>> select complete infinite box

    • It is better to have a distance between the inner point and outer point of the infinite box

      InfiniteBoxCube(size=['300',

                                           '340',

                                '300',

                          '340',

                                '300',

                               '340'])

    • In your case, it is better if you create a face (two faces) in the middle of your device. Like Flux use these faces to create the cut (in the project that you send me, Flux use the mesh to create a cut).

     

    Best regards.

     

     

    Unable to find an attachment - read this blog

  • Andoni Garcia
    Andoni Garcia Altair Community Member
    edited April 2020

    • Infinite box, when you build the infinite box, it is better to use the command “complete infinite box” to build the face and volume. To do it, select the infinite box >> right click>> select complete infinite box

     

    OK! Could you specify please why have I to do that? Why is it not enough just creating a infinity box?

     

     

     

    • It is better to have a distance between the inner point and outer point of the infinite box

      InfiniteBoxCube(size=['300',

                                           '340',

                                '300',

                          '340',

                                '300',

                               '340'])

     

    Perfect.

     

     

     

    • In your case, it is better if you create a face (two faces) in the middle of your device. Like Flux use these faces to create the cut (in the project that you send me, Flux use the mesh to create a cut).

     

    In XZ and YZ planes?

     

    I started drawing this tube due to the fact that I didn't get solve some errors that came to the cooling holes of this geometry.

    image.png.079071d4338cf73c4450514cc0f1b84c.png 

     

     

    I've noticed that the error arises when I create the upper horizontal hole of the tube that connects the vertical holes, the automatical detection of cuts, doesn't create all the detected holes, so next to this I created the missing electric loops.

    Finally I checked the physics and it seems that this last step breaks the connection between the 2 terminals, i.e., it detects only 1 terminal. 

    I would like to add that before creating this hole, the automatic creation of cuts does create all the holes of the sistem, I don't need to appeal to the 'manual' Electric Loop creator.

     

    image.png.055f4a3bc1c279fb8c8940997dd57efc.pngimage.png.fe3334800b3a78f1ac75ce6f36050df5.png

     

    I'll read and try all your advices, let's see if I get a solution. Thanks lot Abdessamed.

     

    Best regards,

    Andoni

  • asoualmi
    asoualmi
    Altair Employee
    edited April 2020

    Hi,

    You are welcome.
    About the infinite box, the command 'complete the infinite box' avoid you to create the faces and volumes.  Also in the case of the device where there is a peridocity, you don't need to create a  linked mesh (it is created automatically when you sue the command 'complete infinite box'.
    Keep me informed if this solve the problem.

    Best regards.

  • Andoni Garcia
    Andoni Garcia Altair Community Member
    edited April 2020

    Hi,

    You are welcome.
    About the infinite box, the command 'complete the infinite box' avoid you to create the faces and volumes.  Also in the case of the device where there is a peridocity, you don't need to create a  linked mesh (it is created automatically when you sue the command 'complete infinite box'.
    Keep me informed if this solve the problem.

    Best regards.

     

    These are the steps I've done:

    - I created the tube geometry (body & holes)

    - Clicked 'Complete Infinity Box' & Assign volume regions

    - Do the meshing

    - Create the circuit & assign terminals

    - Physical check:

    image.png.57625c7e00b6d42ae673c6485c602257.png

     

    When using Electric Loop,  I made the following steps:

    'Automatic creation of cuts', 'Electric Cut creator' (ElectricLoopCut_3) & once again checked physics:

    image.png.573f82a50b70a52b182fc325abf24ed6.png

     

    image.png.d49e5d25d1e53b1a62f93b64959227ed.png

     

    After all this, it is necesary to create once again Electric Loops?

    Here it is this file:

     

    Thank you, once again.

    Andoni

     

    Unable to find an attachment - read this blog

  • asoualmi
    asoualmi
    Altair Employee
    edited April 2020

    Hi,

    Analysing your project, you don’t need to use a cut. You don’t need to create a cut because there is air gap between the different parts of the device. This means that it doesn’t form a closed loop. See attached PDF file for more details.

    The message that you get when you d heck physics, is a warning. this don't stop you to solve the project.

     

    Best regards.

    Unable to find an attachment - read this blog

  • Andoni Garcia
    Andoni Garcia Altair Community Member
    edited April 2020

    Hi,

    Analysing your project, you don’t need to use a cut. You don’t need to create a cut because there is air gap between the different parts of the device. This means that it doesn’t form a closed loop. See attached PDF file for more details.

    The message that you get when you d heck physics, is a warning. this don't stop you to solve the project.

     

    Best regards.

     

    Hi Abdessamed.

     

    Okay, I didn't done any electrical loop but the problem persist.

    This is the error message from the solver.

     

    image.png.0ad9970df39a7ed84cafb496460e6084.png

    I've done all that you've adviced before solving, do you get results with the file I'd sent?

    (Create a face in the middle of the geometry, Complete Infinite Box). I'm drawing through the 'Modeler Context', I don't think so but is there any construction error there?

     

    Never tire of repeating, thank you so much.

    Unable to find an attachment - read this blog

  • asoualmi
    asoualmi
    Altair Employee
    edited April 2020

    Hi,

    The error message come from the fact that there is a singular matrix. To avoid this problem, you need to change the mesh.

    You will find attached Flux project ready to mesh and solve. I change the mesh

    • I deactivate the aided mesh

    • I assign mesh point to all the points of the device

    • I mesh the device again

    With these modifications, I reached to solve the project.

    Best regards.

    Unable to find an attachment - read this blog

  • Andoni Garcia
    Andoni Garcia Altair Community Member
    edited April 2020

    The error message come from the fact that there is a singular matrix. To avoid this problem, you need to change the mesh.

     

    Good morning Abdessamed, 

     

    To avoid future problems, I would be so grateful if you could explain me what is a 'Singular Matrix' a little more in depth. When can I localise this error?

     

    On the one hand, I can understand that Flux can´t solve errors made by geometry, or a wrongly assigned physics, but a mesh error...

    Wouldn't it only influence in calcules precision?

    Sorry but I'm in two minds. 

     

    Thank you so much for your support. 

  • asoualmi
    asoualmi
    Altair Employee
    edited May 2020

    Hi,

    A matrix is singular if and only if it has a determinant of 0. This means that When Flux try to solve the equation, found an error because the determinant is equal to zero.

    About the fact Flux can’t solve the mesh problem, there is not a command which allows Flux to correct the mesh in the event of a mesh defect.

    If you want to see the mesh defects, you can do it once the mesh is done. Go to the:

    • General data

    • Select Mesh

    • Select mesh defect >> right click, add to visualization

       

    Best regards.

  • Andoni Garcia
    Andoni Garcia Altair Community Member
    edited May 2020

    Hi,

     

    I've been simulating with that solid conductor  (secondary terminal of a transformer) WITHOUT cooling holes and coupling the primary winding. I didn't have any problems at all.

     

    Secondary terminal:

    image.png.079071d4338cf73c4450514cc0f1b84c.png

     

    The problem arised as soon as I simulated the same system, using the secondary with the cooling holes instead of the solid one:

     

    <?xml version="1.0" encoding="UTF-8"?>image.thumb.png.dd6a50d48d108d2e5e47f59997a8fa86.png

     

    I've followed the same steps that I'd done with the solid one. I checked the physics and it advises me to create the Electric Loops (as other occasions), but when I run the solver, unlike other times it stops changing the warning to an Error:

     

    <?xml version="1.0" encoding="UTF-8"?>image.thumb.png.8468dc31aa3061e1e2270998ad50e101.png

    image.png.f528c03b516d7618146effe23cc37eac.png

     

    You can get the file here below :

     

    Unable to find an attachment - read this blog

  • asoualmi
    asoualmi
    Altair Employee
    edited May 2020

    Hi,

    I think the problem come from the mesh that you use particularly in volume 5. I modified the mesh of the device. You will find attached the new Flux project.

     

    Best regards.

    Unable to find an attachment - read this blog

  • Andoni Garcia
    Andoni Garcia Altair Community Member
    edited June 2020

    Hi,

    I think the problem come from the mesh that you use particularly in volume 5. I modified the mesh of the device. You will find attached the new Flux project.

     

    Best regards.

     

    Hi Abdessamed,

     

    Thanks for the response but it also doesn't solve the file at this way.

    image.png.ce8a0ce5d93f25378eaf9b090115c4e5.png

     

    I would like to ask the criteria you used in the meshing.

    I saw that you deleted the secondary winding (& meshed with 'Medium' mesh') and changed the primary winding mesh to 3.5mm.

     

    Do you use any kind of calculation?

    Thanks,

    Andoni

    Unable to find an attachment - read this blog

  • Andoni Garcia
    Andoni Garcia Altair Community Member
    edited June 2020

    Hi everyone,

     

    I corrected the electric-loop problem, and I tried to solve the file.
    The thing is that an error 49 has appeared, I think that is related with the meshing:

     

    Anyone can help me, please?
    Best regards,

    Andoni

    Unable to find an attachment - read this blog

  • Andoni Garcia
    Andoni Garcia Altair Community Member
    edited August 2020

    Any help?

     

    Hi everyone,

     

    I corrected the electric-loop problem, and I tried to solve the file.
    The thing is that an error 49 has appeared, I think that is related with the meshing:

     

    Anyone can help me, please?
    Best regards,

    Andoni

     

    Unable to find an attachment - read this blog