Partially filled pipe calculations

[Robster963]

Hello,

How do you calculate (formulas) partially filled vertical pipe flow rate? I have attached a simple sketch. water is gravity fed through a 36 inch tall vertical pipe and thru a horizontal pipe say 12 feet to a pit underground. The pipe size is 10 inches. I understand for horizontal runs, you can apply Manning formula. Any help for vertical pipe is appreciated. Thanks

 

[MJCronin]

Calculations for vertical gravity flow has been been discussed before on these fora.

It was in reference to sizing piping for storage tank overflows ....

MJCronin
Sr. Process Engineer

 

[Robster963]

MJCronin,

Was it for partially filled vertical pipe?

 

[LittleInch]

This is one of my archived threads as its so good.

https://www.eng-tips.com/viewthread.cfm?qid=409750

But it's all about the Froude number.

You won't get 60% full.

How long is the 36" pipe?



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