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Mixing of two air flow at different pressure

  1. Jun 6, 2015 #1
    Mixing Device.jpg

    Hi Friends! Here is my query :

    I have two source of air supply with different pressures, temperatures and with different mass flow rates.
    Input 1: P1,T1,m1.
    Input 2:P2,T2,m2.
    Output: P3,T3,m3.
    P,T and m refers to pressure, temperature and mass flow rate respectively. If the mixing is being done in adiabatic way how to obtain final pressure and final temp of air(P3,T3).
    Open the link

  2. jcsd
  3. Jun 11, 2015 #2
    Thanks for the post! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
  4. Jun 11, 2015 #3
    I don't know if you still need an answer to this but maybe someone else would like to see an answer too.

    You just need to use Bernoullie's equation twice. Once for two of the three sections and another time for two sections from which one must be different than those sections from the first equation. And of course you'll need to have some given pressure and velocities since, obviously, you can't solve a system of two equations with nine unknowns.
  5. Jun 14, 2015 #4


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    Put a control volume around the mixing T. The enthalpy out is equal to the enthalpy in.

    You can treat the two flows separately. There is some amount of energy lost by the flow coming in at a higher temperature and gained by the flow coming in at a lower temperature. The temperature of the two are of course, the same after they've mixed. So just calculate how much energy is exchanged so that the temperatures are the same and you have the enthalpy out for each component.
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