volume flow rate inlet outlet

[Dan_Margulius]

Hello,

Form what I understand the volume flow rate should be tha same at inlet and outlet.

In my model there is 1% percent difference between the two. 

What could be the problem?

Thanks

Dan

[apolo_vanderberg]

Dan,

 A 1% error is typically more than acceptable for Engineering applications. As systems get more complex we will typically strive to ensure we are within 5% or less.

[Dan_Margulius]

Hello Apolo,

Thank you for the answer. 

Can I improve this relative error? Maybe change the Advection? or improve the mesh? 

Thanks

Dan

[apolo_vanderberg]

Dan,

  What error % were you expecting?

Advection Schemes and mesh refinement are typically things to consider when trying to improve this however due to the fact that this is numerical approximation I would not expect to get 100% accuracy.

[Dan_Margulius]

Probably I would expect something very close to 0.
There are mathematical equations behind this which cannot be bend.
Thanks
Dan

[OmkarJ]

Dan, 

Are you sure you have converged the solution? How about running 500 iterations more? 

Have you monitored the points and assessed their plots? ie, are they flat? 

What is your mass imbalance?

OJ