Blood drop impacting a solid horizontal surface (glass)
 

I am trying a blood droplet in fluent using Volume of Fluids (VOF). Patching blood as a sphere inside a highly refined mesh with pressure inlet boundary conditions on the surroundings with horizontal wall (no slip boundary condition and specifying a static contact angle for blood plus introducing surface tension). time step of 1e-6 is used

the problem lies in the results. when the blood droplet impacts the surface. it makes a circular pattern, but as the iterations proceed it starts to deviate from this forming a near square (which is a the domain i am using 18*18*4 mm with a drop diameter of 3.2mm) and after that it separates into different layers. after separating into circular rings/layers the blood keeps on travelling on the horizintal surface.

according to experiments it should be a circular pattern and should stop. it is entirely opposite of it as it is travelling and not in a circular manner. can anybody help me in this. any help or suggestion is highly appreciated.