Press fit analysis

Punith
Punith Altair Community Member
edited October 2020 in Community Q&A

Hello everyone,

basically I wanted to simulate the pressfit. I dont know if this is the right way to do. I already worked with the basic tutorial existing in website using PCONT card where we define the clearence. In my model there is a clearence already included. So I thought of trying with non-linear quasi static large deformation and I ended with an error. I have attached my model.  Also what is the better way to simulate pressfit ( I want to simulate the complete pressfit process). I have no knowledge with Radioss explicit solver. Please help me.

 

Thanks and regards,

Punith Guptha

 

 

«1

Answers

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited November 2020

    Dear Punith,

    Please have a look on video attached.

    Are you looking for the same?.

     

    Unable to find an attachment - read this blog

  • Punith
    Punith Altair Community Member
    edited May 2018

    Hi Ganesh,

    yes some thing like this. Can you help me out?

     

    Regards,

    Punith

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited May 2018

    Hi @Punith

     

    Please refer to the below post:

     

  • Punith
    Punith Altair Community Member
    edited May 2018

    Hi Prakash,

    I already referred this example. It was not helpful. Can you review my model attached and give me a feedback?

    Regards,

    Punith

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited May 2018

    @Punith

     

    OK, I will get back to you soon. 

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited May 2018

    Hi @Punith

     

    Can you run with LGDISP= 1 (large displacement analysis)?

  • Punith
    Punith Altair Community Member
    edited May 2018

    ok will try it.

  • Punith
    Punith Altair Community Member
    edited May 2018

    Got this ERROR

     

    *** ERROR # 4965 ***
     Maximum number of time increment cutbacks reached,
     analysis aborted.

     ANALYSIS COMPLETED.

     *** SOME ERRORS WERE REPORTED DURING THE RUN,
     *** PLEASE VERIFY RESULTS AS THEY MAY BE INVALID.

     *** SOME ERRORS WERE REPORTED DURING THE RUN,
     *** PLEASE VERIFY RESULTS AS THEY MAY BE INVALID.


     *** PROGRAM STOPPED: FATAL ERROR(s) ENCOUNTERED.


     ==== End of solver screen output ==== 


     ==== Job completed ==== 
     

  • Punith
    Punith Altair Community Member
    edited May 2018

    Hello @Prakash Pagadala

    first of all, I would like to know if this is the right way to simulate the press fit. My component is basically a axisymmetric component with slight variations. So initially I wanted to work with a small section to reduce the time. Any recommendations would be welcome. How about using Geometrical Nonlinear implicit analysis?. If there is a existing interferrence in the model how to define the clearence when PCONT is used?

     

    Regards,

    Punith

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited May 2018

    @Punith

     

    I think the model looks fine,

     

    LGDISP activates Geometric NL analysis, anyways, I will check and get back you with details. 

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited May 2018

    Dear punith,

     

    can you tell me what you have done till so far?

     

    Please do it in  Radioss,

    if possible please share presentation showing your objective of the simulation.

    or else share model file, i will work on it and will update you.

     

     

  • Punith
    Punith Altair Community Member
    edited May 2018

    Dear @Ganesh Munge,

    I dont have any knowledge on Radioss till now. I would like to do it in optistruct first. I have already attached my model files in the first message. It is basically a pressfit of two components disc and rim of wheel. To reduce the solver time, I tried initially with a small crosssection as my component is axisymmetric.

     

    Regards,

    Punith

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited May 2018

    Hi @Punith

     

    I see the problem is with the contact,

     

    Did you create the contact using Auto contact in HM?

  • Punith
    Punith Altair Community Member
    edited May 2018

    Hi @Prakash Pagadala

     

    I did not use autoc contact.

     

    Regards,

    Punith

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited May 2018

    @Punith

     

    OK, with PCONT and stiffness set to HARD, I am able to run the model beyond 60% of the load. I will update the results one the simulation is done. 

  • Punith
    Punith Altair Community Member
    edited May 2018

    @Prakash Pagadala

    thank you so much.

     

     

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited May 2018

    Hi @Punith

     

    I have shared a model file with you, please run the same and check the results,

  • Punith
    Punith Altair Community Member
    edited May 2018

    Hi @Prakash Pagadala

    Thank you so much for the solving the issue. Can you tell me how you modified the timestep?. Also please tell me how can I use rotation symmetry for the same model.

    Regards,

    Punith

  • Punith
    Punith Altair Community Member
    edited May 2018

    Hello @Prakash Pagadala

    the model which you gave worked without any problem. I ran a complete 360 deg model later which is running since yesterday but after 92% of the load there is no further iterations performed. Can you tell me how should I proceed further?Can I get the intermediate result?

     

    Regards,

    Punith

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited May 2018

    @Punith

    sorry I missed your last reply.

     

    Introduce NLADAPT>> DIRECT>> NO. This will change the time step.

     

    You can create symmetric boundary conditions if the load is symmetric and use the same.

     

    Can you tell me how should I proceed further?Can I get the intermediate result?

    Maybe time step is reduced to gradually the load. It is not possible to ramp load when the solver is running. 

  • Punith
    Punith Altair Community Member
    edited May 2018

    The solver is running since more than 15 hours and there is no further iterations perfomed. No increment in the load. But solver is running. I dont understand this.

  • Punith
    Punith Altair Community Member
    edited May 2018

    Should I stop the solver and rerun?

  • Punith
    Punith Altair Community Member
    edited November 2020

    Here is my output file. please have a look. No change since 15 hours. I need the results by Monday. Could you please help me out ASAP?.

    Unable to find an attachment - read this blog

  • Nachiket Kadu_22143
    Nachiket Kadu_22143 Altair Community Member
    edited May 2018

    Here is my output file. please have a look. No change since 15 hours. I need the results by Monday. Could you please help me out ASAP?.

    Dont kill the run. Your solution is done about 92%, wait it will converge.

    Unable to find an attachment - read this blog

  • Punith
    Punith Altair Community Member
    edited May 2018

    Hi Nachiket,

    I think the solver has to perform the iterations until the full  load is reached. But since 15 hours it is in the same 92% load iteration. No Increment in the load. What is the problem?

     

    Thanks and regards,

    Punith

  • Nachiket Kadu_22143
    Nachiket Kadu_22143 Altair Community Member
    edited May 2018

    Hi Nachiket,

    I think the solver has to perform the iterations until the full  load is reached. But since 15 hours it is in the same 92% load iteration. No Increment in the load. What is the problem?

     

    Thanks and regards,

    Punith

    @Punith Never encountered such a problem. How much time it took for the solver to reach 92%?

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited May 2018

    @Punith

     

    As said solver is looking for convergence an timestep is really small

  • Punith
    Punith Altair Community Member
    edited May 2018

    @Prakash Pagadala

    ok I understand that. Thank you for the reply.  Now to avoid such a mistake next time how can I export the intermediate results. For example the solver has performed the iterations upto 92% load now and looking for convergence. But I would like to see my results at 91% load. How can I do that?. Please help me.

  • Punith
    Punith Altair Community Member
    edited May 2018

    Hi @Nachiket Kadu

    it took more than 35 hours to reach 92%. Quite a big model. 

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited May 2018

    @PunithYou can restart a run, see this section on OptiStruct help: Requirements for Restarting