Determine the restrictor pipe size for a run of pipe
Determine the restrictor pipe size for a run of pipe
(OP)
Hello I have been asked to help provide some Civil Engineering Design work, but my main area of experience is Structural. I have some information regarding this assignment but I this is very new to me so I am unclear. Any comments/suggestions are appreciated. I have been asked to determine the restrictor pipe size for a run of pipe.
RE: Determine the restrictor pipe size for a run of pipe
Flow rate?
Lenghts?
Fluid ( water, sewage, gas, air, petrol?~)
Give us a bit of clue here as to what and why you're doing
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Determine the restrictor pipe size for a run of pipe
48" dia HDPE
Flow rate?
Q for 100 yr storm is 6.51 cfs
Q for 10 yr storm is 4.65 cfs
Q for 3 yr storm is 3.50 cfs
Lenghts?
98 ft
Fluid ( water, sewage, gas, air, petrol?~
storm water
RE: Determine the restrictor pipe size for a run of pipe
RE: Determine the restrictor pipe size for a run of pipe
What are you trying to do though? Size a short section of smaller pipe? To what flow are you trying to restrict?
Head loss available?
Diagram / section will add a lot to our understanding.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Determine the restrictor pipe size for a run of pipe
http://files.engineering.com/getfile.aspx?folder=7...
and the plans
http://files.engineering.com/getfile.aspx?folder=4...
I am unsure about the 10 yr max warer surface elevation for the site, so i used the same value for the overall max water surface elev (WSEL)
RE: Determine the restrictor pipe size for a run of pipe
Peter Smart
HydroCAD Software
www.hydrocad.net
RE: Determine the restrictor pipe size for a run of pipe
http://sscafca.org/development/documents/DPM/DPM_4...
orifice coefficient is probably more like 0.6 not 0.8
RE: Determine the restrictor pipe size for a run of pipe
RE: Determine the restrictor pipe size for a run of pipe
ASCE Fundamental Canons:
1. Engineers shall hold paramount the safety, health, and welfare of the public and shall strive to comply with the principles of sustainable development in the performance of their professional duties.
2. Engineers shall perform services only in areas of their competence.
NSPE Code of Ethics for Engineers:
I. Fundamental Canons
Engineers, in the fulfillment of their professional duties, shall:
1. Hold paramount the safety, health, and welfare of the public.
2. Perform services only in areas of their competence.
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RE: Determine the restrictor pipe size for a run of pipe
RE: Determine the restrictor pipe size for a run of pipe
RE: Determine the restrictor pipe size for a run of pipe
Q = CA (2gh)^(1/2)
D = Q ½ / (2.25h1/4)
Where:
Q = outflow discharge (cfs)
C = coefficient of discharge
= 0.8 for short segment of pipe
= 0.6 for opening in plates, standpipes, or
concrete walls
A = orifice area (square feet)
g = gravitational factor (32.2)
h = head, water surface differential (feet)
D = orifice diameter (feet)
I found that this is the formula use from the city design manual to determine the required restrictor diameter. I would like to verify that the orifice area is my initial assumed restrictor diameter. Please let me know if this is correct.
RE: Determine the restrictor pipe size for a run of pipe
Peter Smart
HydroCAD Software
www.hydrocad.net
RE: Determine the restrictor pipe size for a run of pipe
RE: Determine the restrictor pipe size for a run of pipe
Body of the thread:
"I've been asked to do structural design for a bridge, but my background is hydrology and hydraulics. Can anyone tell me how big a beam I need? I think it has to hold some big trucks."
Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East - http://www.campbellcivil.com
RE: Determine the restrictor pipe size for a run of pipe
What you need, to answer the question, is the following:
100 year rainfall data
10 year rainfall data
3 year (?) rainfall data (good luck with that by the way, report back if you're able to find it)
watershed area
watershed land cover (may include soil types, depending on method selected)
watershed time of concentration
unit hydrograph (SCS? Something else?)
regional hyetograph shape, depending on method (Type I? Type II?)
stage-storage relationship for your detention pipes
stage-discharge relationships for your selected outflow control structure
Then you apply the storage-indication method for reservoir routing, which of course you learned in your senior level civil hydrology class. (right?)
tl;dr:
I'm going to go out on a limb, here, and say you're in way over your head, you need to go back to school to be able to answer this question, and your boss needs to be slapped for thinking he can hand this to someone without the proper training. He needs to be slapped with a lawsuit if he stamps it.
Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East - http://www.campbellcivil.com
RE: Determine the restrictor pipe size for a run of pipe
One of the best answers I've seen on this forum yet for this type of question.
RE: Determine the restrictor pipe size for a run of pipe
Don't forget to check tailwater, which is based on downstream hydraulics of the receiving system. For that you'll need a different set of data, and probably a different procedure.
Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East - http://www.campbellcivil.com