Question about time scale constant

- July 11, 2024 at 8:58 am
  
  luna6362
  Subscriber
  
  My turbulence model is RSM. I saw in the guide that the recommended time scale constant for RSM is 0.3. However, when I use 0.3, the number of escaped particles does not increase linearly with the number of tries. For example, with 17,000 particles, the number of escapes is 52; with 20,400 particles, the number of escapes is 36; and with 23,800 particles, the number of escapes is 55. What could be the reason for this?
  What is the purpose of the time scale constant in the random walk model of the DPM ?
- July 11, 2024 at 10:04 am
  
  Rob
  Forum Moderator
  
  Look at the particle trajectories. What changes with altering the time scale? The definition will be covered in the documentation.
- July 12, 2024 at 2:13 am
  
  luna6362
  Subscriber
  
  Hi Rob!
  All the following figures are using the RSM model.
  When using 0.3, the particle trajectories are more concentrated. When using 0.15, the particle trajectories become more dispersed.
  How can I determine which one is the correct particle trajectory result? Is it acceptable to set the time scale constant to 0.15 when using RSM?
  Thank you so much.