Gravity flow
Gravity flow
(OP)
Hello,
I have a question regarding a gravity flow pipe scenario. Water flows through a wide-ish channel at its end it is collected by a 798mm (ID) pipe. I have used the attached Cole-brook White formula to calculate the velocity through the pipe at full flow. I am getting a velocity of about 3.5m/s and a flowrate of 1500l/s with 1% slope(seems high). I want to calculate the level in the pipe for my actual flow of 842l/s. I think i have to swap the diameter terms to the new wetted area e.g. 90% area, 80% area etc to find my 842l/s but i am unsure that its is as simple as this...
Does anyone know how to manipulate the formula to give me what i am looking for?
http://fil es.enginee ring.com/g etfile.asp x?folder=4 567eb47-2d 2a-49ca-a3 eb-43441a7 87a86& file=Coleb rook-brook _White.doc
I have a question regarding a gravity flow pipe scenario. Water flows through a wide-ish channel at its end it is collected by a 798mm (ID) pipe. I have used the attached Cole-brook White formula to calculate the velocity through the pipe at full flow. I am getting a velocity of about 3.5m/s and a flowrate of 1500l/s with 1% slope(seems high). I want to calculate the level in the pipe for my actual flow of 842l/s. I think i have to swap the diameter terms to the new wetted area e.g. 90% area, 80% area etc to find my 842l/s but i am unsure that its is as simple as this...
Does anyone know how to manipulate the formula to give me what i am looking for?
http://fil





RE: Gravity flow
Katmar Software
Engineering & Risk Analysis Software
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RE: Gravity flow
http://www.wq.uiuc.edu/dg/Equations/Mannings.exe
RE: Gravity flow
RE: Gravity flow
For a full pipe 4 x R = 4 x PI X D^2/ (4 x PI X D) = D
It is a lot easier to use Mannings equation !!
RE: Gravity flow
Figure 3.4.1 of the above gives a typical chart for partial full flow.
RE: Gravity flow
I have previously viewed the above datasheets.Manning's is indeed alot easier especially with Bimr's calculator! But for the purposes of my piece of mind, i would like to continue to look at a method of solving this by colebrook white formula. I have attached my method used, from this you can see that i have incoporated a capacity value into the equation, it just isn't working as i had hoped, i always get a value of around 100% flow even if i sub in the Rh value for the D value in the equation. I was hoping somebody could have a look and maybe point out some obvious mistake in methology.
RE: Gravity flow
RE: Gravity flow
RE: Gravity flow