Diffusion of Nano particles through inlet of a channel
 

Hello!

I am trying to simulate the diffusion of nanoparticles at the inlet of a rectangular channel using species transport model. Its polystyrene nanoparticles diffusion to a channel filled with water.

I have enabled inlet diffusion in species transport model and set the diffusion coefficient.
Velocity inlet was defined and the velocity was kept 0m/s since particle flow occurs only via diffusion. and the pressure of the inlet was kept higher than the outlet.

The resulting animation of the simulation was a constant of polystyrene mole fraction along the channel as shown in capture 1 below.

But it should be a polystyrene diffusion starting from the inlet and gradually increasing fraction along the channel.

Hope my question is clear to you.
Can someone please help me figure out the error.
Please help!
Thank you..
Attachment 83724
Attachment 83725
Attachment 83726