Hi Guys

Can some one tell me please what is the relationship between mass flow rate (Ubar) and friction Reynolds number (Re tau). I need to calculate mass flow rate (Ubar) from Re tau. Thanks in advance

Basically I am using periodic/cyclic BC at my inlet & outlet. I dont have U or P given, I have only Re tau. How can I calculte velocity from Re tau and then mass flow rate for my channel flow. Thanks in advance for answer.

cfd novice

ok i read your message cal:mass flow rate: you know density of fluid and modal size volume.this will give. actually this is not correct way but that value near by calculating of original