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Polytropic processes

  1. Oct 31, 2011 #1
    polytropic processes are characterized by pvn = constant.

    are they valid for both reversible as well as irreversible processes?
  2. jcsd
  3. Oct 31, 2011 #2

    Andrew Mason

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    It depends.

    The relationship PV= constant (ie n = 1) for an ideal gas applies for all isothermal processes, reversible or non-reversible (ie. PV=nRT)

    However, the adiabatic condition for an ideal gas:

    [itex]PV^\gamma = K[/itex] applies only to a reversible adiabatic change.

  4. Oct 31, 2011 #3
    thanks Andrew.

    suppose if there is a process in which heat flow is happening and the temperature of the system is not constant, lets assume that polytropic index is in the range 1 < n < γ.

    if the process was reversible, then it is reversible polytropic process and we can characterize it by pvn = constant.

    but what if there was friction or some other sort of irreversibility?
    how do we take that into account? how can we characterize such polytropic processes?
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