General Mechanical

General Mechanical

One-Way FSI help for this Wind turbine

    • erwin
      Subscriber

      Hello, I am trying to do a one-way FSI analysis for an archimedes spiral wind turbine. I'm done with the CFD portion and have successfully imported the pressure load from CFD into Mechanical. My current problem is with regards to getting a solution for my analysis. Here is my current setup which I based off a tutorial wind turbine FSI analysis from Cornell University's EdX course: A Hands-on Introduction to Engineering Simulations.


    • 1shan
      Ansys Employee
      What kind of constraint have you used? I think the edges where all 3 blades intersect should be fixed in all dofs. You could simply use a fixed support. Also duplicate the structural analysis and perform a modal analysis. This will help you identify any unconstrained motion. Not sure but the connection object in the first 2 images looks empty. Why have you used a contact tool if no contacts are defined?

      Regards Ishan.
    • erwin
      Subscriber
      Hello Sir Ishan. Thanks for the reply.
      Regarding the edges where the blades intersect, I was trying to replicate what was done in the Edx course from Cornell University, where a remote point was used and then a remote displacement. I had not considered using fixed support but I will definitely try it according to your suggestion.
      As for the contact tool, I was actually looking for solutions online on why my solution would not converge and saw a few including the contact tool. But I understand now that it is not useful for my case. Thanks for clearing that up.
      Lastly, I'll also look into the Modal Analysis, are there any tutorial videos for a Modal analysis to assess potentially unconstrained motions for my model?

      I really appreciate your time Sir Ishan!
      Regards,
      Erwin.
    • 1shan
      Ansys Employee
      I couldn't find a tutorial to demonstrate but I have added a few images below. You just need to perform a normal modal analysis (plenty of videos on you tube) and then check deformation of the first few modes. As you can see in the images below I had a 1d model consisting of 3 beams but there was no connection between them which is evident from the mode shapes. Also you don't need to construct a new modal analysis from scratch, simply create a duplicate of the original analysis and replace the duplicate with modal analysis(click the drop down arrow on top of static structural in your project schematic).

      Regards.
    • erwin
      Subscriber
      Thank You, Ishan, I'll try your suggestions later and maybe inform you If I find success.

      Regards,
      Erwin
    • erwin
      Subscriber
      Good Day Sir Ishan.
      I have encountered another problem upon trying a modal analysis for the wind turbine.
      As you can see, one blade seems to be heavily distorted for Mode 1. I also checked the results for the other modes, and they also look heavily distorted. I was wondering if this has to do with my current boundary conditions?

      Should I probably remove the rotational velocity condition from my static structural analysis to get a better result from the modal analysis? I would like to get your opinion about the matter because it might be able to help me.

      Regards Erwin

    • erwin
      Subscriber
      Hi Sir Ishan, just to give you an update, I tried removing the rotational velocity condition and the results for the modal analysis still looked the same. I think the "distorted" results have to do with the complexity of the geometry I currently have, given that it has a lot of curvature.
    • 1shan
      Ansys Employee
      The rotational velocity should not make any difference in the modal results (unless you are doing a rotor-dynamics analysis). Turn "On" large deflection under analysis settings and also refine mesh in areas where the curvature is high. You could use a edge sizing with a suitable bias to create smaller elements near the apex of the cone. If this doesn't work, try trim off the high curvature region (near the apex) in space-claim. Also use '@' before mentioning any user, this way he is notified of your comment.
      Regards Ishan.
Viewing 7 reply threads
  • You must be logged in to reply to this topic.