The thermodynamics of real gases at high pressures

For studies of hypersonic flight, the thermodynamics of real gases at pressures up to 15,000 atm and temperatures as high as 3500 K needs to be characterized. Closed-form equations of state are capable of predicting the behavior of real gases to about twice that of the critical density; through use of statistical thermodynamics, high density systems may be examined, though due to lack of experimental data and weaknesses in the analytical methods, virial coefficients may not be available for many cases of interest. Extrapolation techniques for such problems as the characterization of nitrogen behavior to a density of 1000 amagats are discussed.