sphere falling in an infinite liquid medium
 

hello, i am trying to solve a simple problem of a sphere falling in an infinite liquid medium. if i just define the geometry and try to solve the problem, the solver is not taking account of the liquid rising back. and this is also reasonable as how can it come to know the exact physics without we specifying it. i am confused as to how to formulate this problem, such that the solver takes into account of the rising liquid. ie ., volume conservation has to be incorporated.

i will be thankful if you will be giving me some suggestions.

sreenivas