Problems with static mixer simulation (diffusion vs convective mixing)

I am trying to simulate a static mixer to assess its mixing quality through multiple iterations. It is meant for liquids with minimal diffusion such as latex paint in the realm of 750 Pa*s viscosity. I am having difficulty reducing the diffusion within the liquid as i would like convection to be the main mixing mechanism. I have tested higher velocity, higher viscosity, and lower diffusion coefficient and none of them seem to affect the results of the chds simulation. I would like some guidance as to how to remedy this problem or where i am going wrong. Attached is the Comsol simulation file since it may be helpful if a mistake has been made in the setup. Any help would be greatly appreciated.

Thanks greatly for your time and help,
Jon O