This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Minor loss coefficient question

HEY I'm designing chilled water cooling system with closed loop its huge and I'm phasing some Difficulties I don't know if watercad  can handle it but I'm trying any way,  the minor loss coefficient was derived from which equation? and how should I deal with it for valves and pipes??? any help please

Parents
  • Minor loss coefficients are determined experimentally. There are many sources for standard minor loss coefficient values to be used in various situations (tees, bends, valves etc.). The Bentley Hydraulics and Hydrology applications provide many of these standard values in an Engineering Library.

    To view these:

    1. Go to the Components tab.
    2. Select Engineering Libraries.
    3. Expand "Minor Loss Libraries".
    4. Expand "MinorLossLibrary.xml".

    To apply one of these to an element:

    1. Double-click the element to display the Properties dialog.
    2. In the Physical section set "Specify Local Minor Loss?" to True.
    3. Click in the "Minor Loss Coefficient (Local)" input field and click the "..." button.
    4. Choose a minor loss from the Engineering Library and click the Select button.

    The standard minor loss equation is:

    H=K(v^2)/(2*g)

     H = Minor Head Loss
     K = Minor Loss Coefficient
     V = Velocity of Flow
    G = Gravitational Acceleration Constant (about 9.81 m/s^2, or 32.174 ft/s^2)

    The minor loss coefficient applied to the element will be used in the minor loss equation and the result will be displayed in the "Results" section in the field "Headloss (Minor)".

     

    See Also:

    Adding Minor Losses to Pipes

    Modeling minor losses at a valve or a tee

     

    Please elaborate on any other questions you have regarding the system you are modeling.

     

    Regards,

    Craig Calvin

    Bentley Technical Support

    Answer Verified By: A.S 

Reply
  • Minor loss coefficients are determined experimentally. There are many sources for standard minor loss coefficient values to be used in various situations (tees, bends, valves etc.). The Bentley Hydraulics and Hydrology applications provide many of these standard values in an Engineering Library.

    To view these:

    1. Go to the Components tab.
    2. Select Engineering Libraries.
    3. Expand "Minor Loss Libraries".
    4. Expand "MinorLossLibrary.xml".

    To apply one of these to an element:

    1. Double-click the element to display the Properties dialog.
    2. In the Physical section set "Specify Local Minor Loss?" to True.
    3. Click in the "Minor Loss Coefficient (Local)" input field and click the "..." button.
    4. Choose a minor loss from the Engineering Library and click the Select button.

    The standard minor loss equation is:

    H=K(v^2)/(2*g)

     H = Minor Head Loss
     K = Minor Loss Coefficient
     V = Velocity of Flow
    G = Gravitational Acceleration Constant (about 9.81 m/s^2, or 32.174 ft/s^2)

    The minor loss coefficient applied to the element will be used in the minor loss equation and the result will be displayed in the "Results" section in the field "Headloss (Minor)".

     

    See Also:

    Adding Minor Losses to Pipes

    Modeling minor losses at a valve or a tee

     

    Please elaborate on any other questions you have regarding the system you are modeling.

     

    Regards,

    Craig Calvin

    Bentley Technical Support

    Answer Verified By: A.S 

Children