• Amused
  • Angry
  • Annoyed
  • Awesome
  • Bemused
  • Cocky
  • Cool
  • Crazy
  • Crying
  • Depressed
  • Down
  • Drunk
  • Embarrased
  • Enraged
  • Friendly
  • Geeky
  • Godly
  • Happy
  • Hateful
  • Hungry
  • Innocent
  • Meh
  • Piratey
  • Poorly
  • Sad
  • Secret
  • Shy
  • Sneaky
  • Tired
  • Results 1 to 5 of 5

    Thread: Nomograph- based on Mannings Equation

    1. #1
      GHouse's Avatar
      GHouse is offline Senior Member
      This user has no status.
       
      Feeling:
      ----
       
      Join Date
      Oct 2007
      Location
      Rochester,NY,USA
      Posts
      1,190

      Nomograph- based on Mannings Equation

      http://www.tpub.com/content/armyengi...N5465A0078.htm

      This one is not as straight forward as it could be. I have some hard copies that give rate in gallons/ sec or cubic ft/ sec.
      This will give a good idea of gravity pipe flow, it does not account for head pressure, or pump pressure.
      For those you need Bernelli's Equation, a bit more complicated.
      Last edited by GHouse; 05-19-2009 at 07:33 PM.

    2. #2
      icu2's Avatar
      icu2 is online now Administrator ~ WWKC Treasurer
      is usually here but if not I'm
      probably off flying
       
      Feeling:
      Piratey
       
      Join Date
      Feb 2007
      Location
      Poulsbo, WA
      Posts
      23,324
      omg...

      Thanks for sharing!
      You're my hero! You must know how to equate all those numbers to actual
      use... but me... I'm lost.

      How the heck do you figure the Roughness Coefficient to use for a pvc pipe?
      Or a pipe I've heated and bent?

      It's pretty darn cool... but I wish I was better at math...
      --Steve
      Find more about Weather in Poulsbo, WA

      "It is far better to be alone, than to be in bad company." --George Washington

    3. #3
      Otter is offline Senior Member
      This user has no status.
       
      Feeling:
      ----
       
      Join Date
      Oct 2007
      Location
      NW Indiana (zone 5)
      Posts
      793
      Thanks. At first glance I thought this was going to be another one of those "I know what I'm talking about, why don't you?" horrors with no units or definitions, but most of the necessary info is there. Do you have a link to the roughness coefficients for common types of pipe?

      Is "slope" the difference in water levels divided by the length of the pipe? If so this will be very useful.

    4. #4
      GHouse's Avatar
      GHouse is offline Senior Member
      This user has no status.
       
      Feeling:
      ----
       
      Join Date
      Oct 2007
      Location
      Rochester,NY,USA
      Posts
      1,190
      Slope is Rise / Run, or the change in elevation divided by the length of the run of pipe in this case. Roughness coefficents are in any good hydraulic reference, but you only need a few.
      There are great formulas for open channel flow, channels, stone inlets or outlets and weirs.
      Last edited by GHouse; 05-21-2009 at 10:31 PM.

    5. #5
      Otter is offline Senior Member
      This user has no status.
       
      Feeling:
      ----
       
      Join Date
      Oct 2007
      Location
      NW Indiana (zone 5)
      Posts
      793
      Ah, this is for open channels.

      Steve, a quick web search turned up 0.009-0.011 for PVC.
      http://www.lmnoeng.com/manningn.htm

    Posting Permissions

    • You may not post new threads
    • You may not post replies
    • You may not post attachments
    • You may not edit your posts
    •