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Thread: Vi rule

  1. 15-02-2009, 07:48 AM #1
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    Vi rule



    Hi,

    I have question about Vi in screw compressor.
    I want to know why discharge temperature increase if i use a compressor with higher Vi
    Thanks


  2. 15-02-2009, 01:31 PM #2
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    Re: Vi rule

    VI is a subject that needs a bit of study to understand.
    Overcompression or Undercompression occurs when the VI is not correct.
    I would suggest that you read this article. I refer to it often.
    http://www.petroassist.com/Tech%20Kn...ompressors.pdf

    Thank you Mr. Pillis (The author of the article)
  3. 16-02-2009, 05:00 PM #3
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    Re: Vi rule

    NH3LVR Thanks for the link C.D.
  4. 16-02-2009, 06:35 PM #4
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    Re: Vi rule

    If the volume ratio number (the number associated with the Vi) is higher than the optimum Vi, the compressor is over-compressing the gas. This causes the higher discharge temperature.
    If all else fails, ask for help.

  5. 16-02-2009, 08:49 PM #5
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    Re: Vi rule

    Like US Iceman said...more compression pushes the discharge temperature up. Look at the Idael Gas Laws.

    Ken
  6. 17-02-2009, 06:36 AM #6
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    Re: Vi rule

    Hi members

    thanks for your complete answers.
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