Subject: I would like a function for a vortex please.

I am chasing a function for a vortex, for use in a singularity (black hole) 
simulation. I would like to be able to pick the exact point in the vortex that 
a certain object may be. I wish to adapt this function to include mass of 
object, linear direction, linear angle, velocity, and other variables that may 
help in calculating other things such as escape velocity for that particlar 
function. I would appreciate any help, even links to similar research.
Thanks

Re: I would like a function for a vortex please.