Metodika rascheta linii fazovogo ravnovesiya khladagentov ot troynoy do kriticheskoy tochki



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Abstract

Within the framework of the method offered the equilibrium line calculation is based on the set of interconsistent equations including the equation of elasticity line ps = ps(Ts) (where ps is the pressure on the elasticity line; Ts is the temperature on the elasticity line) as well as the equations describing the vapor r- = r-(Ts) and the liquid r+ = r+(Ts) branches of saturation (where r is density). At that the equation for r- = r-(Ts) is derived on the basis of the Clayperon-Clausius modified equation that includes “apparent” heat of vaporization r* linked with the heat of vaporization by dependence r = r*(1 - r-/ r+). The line of the phase equilibrium is calculated using the method offered. It meets the mean diameter rule of saturation line fd in accordance with “final” scaling: fd ~ t2b, where b is the critical index of saturation line. The method was tested on the example of the calculation of the phase equilibrium line for R32 at the range of temperatures from triple to critical point. It was shown that the error of ps and r± calculation corresponds to the experimental error of these values in the range mentioned.

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References

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