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Water vs. water/glycol flow rates

  1. Jan 22, 2015 #1
    I'm trying to get a rough idea of how flow rate through a round, sharp edged orifice is affected when a fluid is water/glycol versus pain water. In this circumstance, it's 30% water, 55% Dihydroxydiethyl Glycol and 15% Polyalkylene Glycol. I don't need exact numbers at this point, just a qualitative direction. My gut is saying that the glycol component is going to require the orifice to be larger than for plain water at the same pressure and flow rate. Can anyone provide what they think would be a safe estimate for how much larger to go to get an equivalent flow rate of the water/glycol versus water, or provide any online resources that may help?

  2. jcsd
  3. Jan 22, 2015 #2


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    Flows thru orifices have been studied extensively:


    The mass flow rate thru an orifice is inversely proportional to the square root of the mass density of the flowing liquid. It's not clear what the mass density of your water-glycol mixture is compared to that of pure water.
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