Significance of Loading Scale Factor in Time History Fatigue Analysis

- May 3, 2019 at 8:39 am
  
  shamik062
  Subscriber
  
  Hello everyone,
  
  I am fairly new in using Ansys fatigue tool. There is a "Loading Scale Factor" to specify during fatigue analysis with Time History Data. I have failed to understand what is the significance of it ? Or how to specify the factor for any available data. I am attaching a file of History data for which the "Loading Scale Factor" is used as 0.005 in an example. My question is how to calculate it for any given loading?
  
  Any help is highly appreciated.
  
  Thanks in advance.
- May 3, 2019 at 9:14 am
  
  jj77
  Subscriber
  
  See this document for some good info about fatigue in Ansys:
  
  As for your question it says:
  
  "
  
  The user may also specify a Loading Scale Factor that will scale all stresses, both alternating and mean by the specified value. This value may be parameterized. Applying a scale factor is useful to avoid having to solve the static model again to see the effects of changing the magnitude of the FEM loads."
- May 4, 2019 at 12:39 pm
  
  shamik062
  Subscriber
  
  Thank you for replying.
  
  I have read the document you are talking about. The significance of the "Loading scale factor" is well understood in case of a constant amplitude loading. But I don't understand the significance of the that factor in case of History Loading (like the one in the .dat file I have attached). For that particular loading the factor is taken as 0.005.
  
  My question is if I have any other random load history file, how I am going define or calculate that factor? What is the impact of that factor on my results?
  
  I have also attached the image where I have found the example I am talking about (Point No 34).