5/16/ 1/2" flow rates

[markcasper]

There is a 5/16" line running on the ground, the flow rate is 7 gallons per hour. If it was a 1/2" line and it was laying right next to it, how much would the flow rate be?

[ennismaple]

My math says you're on an average 1.5% slope to get 7 GPH out of a 5/16" pipe (using Manning's equation). By upgrading to a 1/2" pipe (assuming the same roughness coefficient) you should get 24.5 gallons per hour.
3/4" pipe = 72.3 GPH
1" pipe = 156 GPH

It's not a straight linear relationship between end area and flow because the wetted perimeter (i.e. friction) factors into the equation but it's not far off to say by doubling the end area of the pipe you double the flow.

[markcasper]

Thanks ennismaple! I won't wonder how you came up with that, but I know it will be right.

The flow rate in the 5/16" was a proven number. Now I have to figure how much longer it will take a 3/4" line to unthaw versus a 1/2" :)

[Amber Gold]

I didn't do the math, but Ennismaple's on the right track. If you're pumping the sap instead of letting it flow by gravity, you'd get higher flow rates.

So if you want the pipe "unthawed", do you want it to stay frozen??

[ennismaple]

Thanks ennismaple! I won't wonder how you came up with that, but I know it will be right.

All that high priced learnin' gets put to use sooner or later!

Let me know how close the actual number are to what I've estimated.