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clear pipe, pumping demo

hot rodhot rod Member Posts: 7,077
A portable display I built for my trainings. The one side shows how P/S works, and the reverse flow between the close tees, when you adjust the flow rates. Also the issues with entrained air in the clear plastic pump volutes. It demonstrates air, dirt, and magnetic separation.

The demo clearly shows how the flow transitions from turbulent to laminar when you ramp down the pump speed. When flow goes laminar the outer boundry of fluid stops completely and a small core of fluid moves through it. It becomes clear how heat transfer would drop considerably when the fluid slows below turbulent conditions.

On the reverse side it shows a Sep4 air, dirt, magnetic and hydro separation,

Also a partially clear heat exchanger that shows how the micro bubbles cling to the HX wall without adequate flow and micro bubble elimination?

The Caleffi road show travels across Iowa next week.
Bob "hot rod" Rohr
trainer for Caleffi NA
The magic is in hydronics, and hydronics is in me


  • Mike KusiakMike Kusiak Member Posts: 604
    Laminar vs turbulent

    Very nice display.

    How do you make the transition from laminar to turbulent flow visible with a clear liquid?

     I understand the difference in velocity between the tube boundary and the center section in laminar flow, but how do you actually see whats happening in the demonstration?
  • GordyGordy Member Posts: 7,122

    Display Like Mike wondering how you do the flow visual? Dye injection some where?
  • hot rodhot rod Member Posts: 7,077
    I use some glycol

    to protect it from freezing in the truck. The brand I use is bright green, so that gives me some color. I also have some food coloring to add to the different piping sides of the separators to show how the fluids stay separate until both circs are running.

    And I connected a small aquarium air pump. When you pump air into the fluid stream you can see where the movement is and where the boundry layers are still. It also shows how the tiny micro bubbles adhere to the collision media inside the separators.

    When the fluid is turbulent it actually corkscrews thru the pipe, almost looks like a drill running inside the tube.

    I'll try to do some You Tube Videos later this week.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
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