Basic help

Hi Dear All,
I study LBM from last few months and still it’s new for me. One i can not find enough gap for future research work using this method, it’s look to me that it’s developed from long time by so many great researchers. So i try to use this method for some practical problems.But i have some basic questions that i not fully understand. If some can give the answeres with some logic and from physical aspects it will be highly appreciated.

  1. What’s the main difference between particle distribution function (f) and equilibrium distribution function(f(eq)). Which one play a major role in LBM.
  2. What’s the main logic behind single relaxation time parameter (t) in LBM. Can the LBM fully depend on this parameter or up to some extend.
  3. Not from programing point of veiw. What’s the main difference between streaimg and collison steps in LBM.
  4. What’s the basic theme behind speed of sound.
    Can anybody help to explain from physical point of view the importance and existence of above questions.
    Thanks in advance
    Best Regards
    Yuan Chao Mei

Hello
I join to/in this question :slight_smile:
I really want to heard explanation.

I think that you should read a basic article or book about the theory and background of LBM, e.g., the book by Succi or Sukop & Thorne. Basic articles can be found here. It would be too much work to answer all your questions in detail here.