How can I caculate flowrate for recangular copper tube?

[admin]

I will check it latter, but please note that you must enter pressure in absolute values.

[admin]

Here is what I get from pressure drop calculator:
http://www.pipeflowcalculations.com/pressuredrop/


Pipe pressure drop calculator CALCULATION REPORT
1. volume flow rate (q): q = 48.404667 l/min
2. weight flow rate (w): w = 2904.2837 kg/h
3. pipe length (L): L = 11 m
4. pipe diameter (D): D = 14.594595 mm
5. pipe roughness (kr): kr = 0.1 mm
6. density (ρ): ρ = 1000 kg/m3
7. kinematic viscosity (ν): ν = 1.004 mm2/s
8. dynamic viscosity (μ): μ = 0.001004 Pas
9. K factor - minor lossed coefficient (K ): K = 0.0
10. velocity (V): V = 4.822378 m/s
11. cross section area (A): A = 167.29155 mm2
12. friction coefficient (f): f = 0.019397806
13. Reynolds number (Re): Re = 70100.26
14. boundary layer (δ): δ = 0.052656855 mm
15. pressure on the pipe start (p1): p1 = 3.013 bar
16. pressure on the pipe end (p2): p2 = 1.313 bar
17. pressure drop (p1-p2): p1-p2 = 1.7 bar
18. channel height (H): H = 10 mm
19. channel width (W): W = 27 mm

Please tell me which friction factor does your colleague use?
Note that ydraulic radius calculated here is 14.6 mm.

Also Kr = 0.1 mm for copper tube might be to big - maybe your colleague is using smaller pipe rougness.

[DavidE]

Hello again!

Many thanks for your answer, and really sorry for this very late reply. Actually, I was looking for your reply soon after I posted the message, but did not realize your answer had gone onto page 2. I have just returned from holiday and looked again, and then noticed there was now another page. I am now quite confident in the results of the calculation, as my colleague has confirmed he is using a lower copper pipe roughness factor. Thanks again for your great help!

Best regards,
DavidE

[admin]

Thank you DavidE,

Good luck!