On 05/18/2016 3:44 PM, Rick Rayfield wrote:
replying to MLD, Rick Rayfield wrote:
lot

Quick calculation ---pi/4 washes out: Area of a 6" pipe-6^26. Area of
two 4" pipes is 2*4^22. 36/32=1.125--so 6' pipe has about 12.5% more flow area
than two 4" pipes....

....

Most of the answers address the problem presented. But the question
asked was about the "volume"of the four and six inch diameter pipes. Roughly, with a
cross section of 12 square inches, a foot of four inch diameter pipe has
144 cubic inches,...[rest elided for brevity]

But the volume is simply Area * Length so the length also cancels out if
ratio so the volume ratio is identically the cross-sectional area.

Precise numbers are easily available from pipe tables online...

http://www.engineeringtoolbox.com/ansi-steel-pipes-d_305.html

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