A FORTRAN package for the calculation of the three isentropic exponents - based on the Redlich-Kwong equation of state
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Krikkis, RN
(EN)
Kakatsios, XK
(EN)
It has been shown that the isentropic change of real gases can be described with very good accuracy by the ideal gas isentropic change equations, provided that the isentropic exponent k = c(p)/c(upsilon) contained in these equations is replaced by the three new isentropic exponents k(Tupsilon), k(Tp), k(pupsilon) in the way shown below: pupsilon(kpupsilon) = const Tupsilon(kTupsilon - 1) = const p(1 - kTp)T(kTp) = const. The values of the three isentropic exponents can be easily calculated if the thermal (p = p(upsilon, T)) and the caloric (c(p) = c(p)(upsilon, T), c(upsilon) = c(upsilon)(upsilon, T)) equations of state for the real gas considered are known. The present work provides a general program for approximating the values of the above exponents for real gases for which no detailed thermodynamic data are available and it is based on the Redlich-Kwong equation of state.
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