Source Value wrong UDF?
 

Unfortunately I run out of ideas with the help of this forum and User Guide. Therefore this new thread.

I have a 2D pipe devided in 3 areas (upstream, middle, downstream).
At the Inlet I set a specific value for my UDS (C). The whole domain in the middle acts as a source. I want to reduce my C by 10% from Inlet to Outlet

Source formula for UDF:

source = -0.1* C / sourcevolume;

C=UDS Value in Cell
sourcevolume = volume of domain "middle"

The results show, that my UDS Value is reduced by 85%. Any idea, why this is happening? I run out of ideas


PS:
The Outlet condition fopr UDS is FLux=0 so this shouldn't have any effect on the Value of C and the Diffusion = 0 as well.