Fatigue Life Result

- October 19, 2023 at 7:10 pm
  
  louiee1907
  Subscriber
  
  1 - I did modal an analysis to calculate natural frequencies.
  2 - After the modal, I did a harmonic analysis (0-2000 Hz) in X-Y-Z directions separately using 1 g unit acceleration.
  3 - I connected every harmonic analysis with nCode SN VibrationPSD and since I have PSD datas (g^2/Hz), I did random psd analysis in nCode. (Duty Cycle is used for analysis and 1500 repeats is used for every directions.)
  4 - I put my PSD datas in multicolumn, then I connected to Vibration Generator.
  5 - Material is Aluminium Alloy. Method : Dirlik
  Although I did everything, my life result is 3.721 repeats. It is very low. Am I wrong? I cannot convert 3.721 to hours. Please, can you help me about this problem?
  Is my method wrong or not?
- October 20, 2023 at 1:04 pm
  
  Ashish Khemka
  Forum Moderator
  
  Hi Louie,
  It might not be possible for Ansys employees to comment more on if the approach above is correct or not. Please wait for other forum members to comment more.
  
  Thanks,
  Ashish Khemka
  - October 20, 2023 at 3:23 pm
    
    louiee1907
    Subscriber
    
    Thank you sir, but noone writes any solution. I try to do fatigue analysis in nCode, I think nonone does not know, so thanks to you I can be successful. How can I learn this method is true or not? Please, I need your help. I try to do fatigue analysis for weeks.