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formula for 1" or smaller pvc volumes
3

formula for 1" or smaller pvc volumes

formula for 1" or smaller pvc volumes

(OP)
i need to figure out what the volume in GPM of a 1" pvc pipe 36" long at 3 ft/sec is. help please show math. also for a 3/4" pvc pipe same lenght and ft/sec.

RE: formula for 1" or smaller pvc volumes

You need 180 feet of pipe ( 3 ft/sec x 60 sec/minute).
Cap one end, stand upright on a scale to get the dry weight, then fill with water and re-weigh. Weight of water is 8.32487 pounds per gallon at 68 degrees F (measured in air at sea level). To double-check, empty the filled pipe into measuring buckets.

It's also theoretically possible to use the ID (inside diameter) of the pipe to calculate the volume. One US liquid gallon, by law  = 231 cubic inches. If you know the pipe schedule (Schedule 40 is commonly used), search for pipe dimension tables.

RE: formula for 1" or smaller pvc volumes

Q = v x A

A = Pi x R^2

D = 1 in = 0.083 ft

R = D/2

V = 3 ft/sec

1 cubic foot = 7.48 gallons (US ?)

1 minute = 60 seconds


flow = 7.3 GPM

The length of the pipe is not relevant

Do you really need to ask this ?

RE: formula for 1" or smaller pvc volumes

BRIS, I am sure that Ken only specified 180 ft of pipe to simplify the horrifically complicated math involved in this problem. In fact any multiple of 180 ft (eg 360 ft etc) could be used.  The only alternative for lalvarez, if he doesn't want to use so much pipe, is to use his high school math and his brain.

Katmar Software
Engineering & Risk Analysis Software
http://katmarsoftware.com

RE: formula for 1" or smaller pvc volumes

Katmar - I didn't see ken's response before making my facetious comments. The horrendous maths result from working in imperial US units. We don't have a problem working in SI units, always providing the pipe ID is not specified to some US schedule.

Brian

RE: formula for 1" or smaller pvc volumes

BRIS, 'imperial US units' is confusing. Imperial inches & gallons are slightly larger than the US measures.
Best avoid advanced mathematics - simply empty the water from 180 feet of pipe into a large, graduated bucket.

RE: formula for 1" or smaller pvc volumes

laughtearsroflrofl2  rofl3

cheers

RE: formula for 1" or smaller pvc volumes

But Imperial ounces are smaller, not larger than US ounces.
This is a point that Canadian educators were never aware of with the result that generations of Canadian students were taught the wrong conversion from imperial gallons to US gallons.
respectfully

RE: formula for 1" or smaller pvc volumes

All,

Once we have the flow in imperial GPM, can we make it veddy veddy British and calculate the flow in furlongs per fortnight?

Please show the math.

regards, John.

RE: formula for 1" or smaller pvc volumes

Furlongs per fortnight only gives us a unit of velocity.  We'll need to know the other two dimension units you require in order to calculate a flow rate.  The simplest would obviously be cubic furlongs per fortnight, will that suffice?

RE: formula for 1" or smaller pvc volumes

Acre feet per fortnight are the correct units for volume. You don't get many down a 0.045 chain long 25mm diameter pipe.

RE: formula for 1" or smaller pvc volumes

Ahhh yes,

I meant to suggest that we calculate the flow VELOCITY in furlongs per fortnight?  However, mass flow calculated in cubic furlongs per fortnight has a certain veddy British charm.  I like it.

Regards, John.

RE: formula for 1" or smaller pvc volumes

I hate to disappoint but all this wealth of knowledge and mathematical analyses are wasted. The guy posting the question has not logged in since posting on the 8th August.

My intensive research into determining the mathematical relationship between diameter and area of a pipe is wasted.


RE: formula for 1" or smaller pvc volumes

He's probably been too busy assembling 180' of pipe ... and trying to find a ladder long enough to reach the top to fill it.

cheers

RE: formula for 1" or smaller pvc volumes

Probably an Architect student

Richard A. Cornelius, P.E.
WWW.amlinereast.com

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