   how to simulate small particles flow down to a rotating duct
  Hi,I want to simulate some balls flow down to a rotating duct, and make a model uploaded in the youtube.com.There is also some information on the following link:http://www.mech.kth.se/mech/static_masterproj.jspThere are some questions troubleing me, I don't konw the coriolis and confugal forces very well. I there any basic models I can study?Thanks for any suggestion.   
  I don't think you mean "confugal". Perhaps you were thinking of "centrifugal"?Centrifugal and Coriolis forces are what are known as "fictitious forces". That is, rather than being fundamental physical forces, they are the result of applying standard physical laws in a non-inertial reference frame (in this case, a rotating reference frame). Unless you have chosen a very strange way of implementing this project, you don't need to worry about them; get the rest of the physics right, and they will just "happen".   ;Quote:Original post by SneftelI don't think you mean "confugal". Perhaps you were thinking of "centrifugal"?Centrifugal and Coriolis forces are what are known as "fictitious forces". That is, rather than being fundamental physical forces, they are the result of applying standard physical laws in a non-inertial reference frame (in this case, a rotating reference frame). Unless you have chosen a very strange way of implementing this project, you don't need to worry about them; get the rest of the physics right, and they will just "happen".-------------------------------------------------------------------------------Yes, that is "centrifugal" force : )I want to get the acceleration, velocity and position of the balls in the world coordinates or inertial frame.Don't thinking about the Centrifugal and Coriolis forces in the world frame?;Quote:Original post by youyingDon't thinking about the Centrifugal and Coriolis forces in the world frame?Nope! They don't exist in the world frame.