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Uniform non-analytical equation of the state of R218 satisfying the fundamental theory of critical phenomena

UDC 536.71

Uniform non-analytical equation of the state of R218 satisfying the fundamental theory of critical phenomena

Kudryavtseva I.V., Rykov A.V., Rykov V.A., Rykov S.V.

Abstract
An equation of the state of R218 is offered. The R218 refrigerant is applied as working medium in refrigerating equipment. The equation of state describes its thermal and caloric properties. It has been compared with other contemporary equations of state. A new crossover function was used in this work. The single-phase area showed the following standard deviations: density δρ = 0.3; isochoric heat capacity in broad vicinity of the critical point δCv = 0.8; isobaric heat capacity δCp = 2.4%; and speed of sound δw = 2.2%. This equation of state provides accurate qualitative and quantitative reproduction of thermodynamic function features both in the regular area and in the critical point’s vicinity.

Keywords: equation of state, heat capacity, R218 refrigerant, thermodynamic function.

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Uniform non-analytical equation of the state of R218 satisfying the fundamental theory of critical phenomena

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