Calculating velocity for partially flowing pipe
 

Hello,

Does anyone know how fluent calculate the velocity for partially full flowing circular pipe? If I do the calculation of velocity from the mass flow rate and water depth at outlet manually, I find different result from what fluent gives as mass-averaged velocity. Any help will be highly appreciated.

Thanks
Tanjina

You can find the details in 22.3.1 for Surface Integrals. Fluent uses basic calculus rules, nothing fancy.