Reply To: Extracting Amount of Sediment Mass Passing through Line Surface

[Rob]

There are a few things to check. 

• The interior zones don't have a normal so need to be oriented so all facets are aligned. That may or may not alter the +/- sign but more critically means all of the facets on the surface are +/- and can't cancel each other out. 
• Convergence - has the model been converging? Does the total mass in the domain add up to the injection?
• As there's a position difference in the 3 lines, are you seeing a lag effect in the values. Look at the upstream section to see why that might be occuring.