Thermodynamic Properties of Vapors from Speed of Sound. (21st July 2014)

• Record Type: Journal Article
• Authors: Bijedić, Muhamed; Begić, Sabina
• Other Names: Lucia Angelo Academic Editor.
• Is Part Of: Journal of thermodynamics. Volume 2014(2014)
• Publication Date: 2014-07-21
• Subjects: Thermodynamics -- Periodicals; Thermodynamics; Periodicals; Electronic journals; 536.7
• DOI: 10.1155/2014/231296
• Languages: English
• ISSNs: 1687-9244

Abstract

Abstract : A numerical procedure for deriving the thermodynamic properties( Z, c v, andc p ) of the vapor phase in the subcritical temperature range from the speed of sound is presented. The set of differential equations connecting these properties with the speed of sound is solved as the initial-value problem inT - ϕ domain( ϕ = ρ / ρ sat ) . The initial values ofZ and∂ Z / ∂ T ρ are specified along the isothermT 0 with the highest temperature, at a several values ofϕ [0.1, 1.0]. The values ofZ are generated by the reference equation of state, while the values of∂ Z / ∂ T ρ are derived from the speed of sound, by solving another set of differential equations inT - ρ domain in the transcritical temperature range. This set of equations is solved as the initial-boundary-value problem. The initial values ofZ andc v are specified along the isochore in the limit of the ideal gas, at several isotherms distributed according to the Chebyshev points of the second kind. The boundary values ofZ are specified along the same isothermT 0 and along another isotherm with a higher temperature, at several values ofρ . The procedure is tested on Ar, N2, CH4, and CO2, with the mean AADs forZ, c v, andc p at 0.0003%, 0.0046%, and 0.0061%, respectively (0.0007%, 0.0130%, and 0.0189% along the saturation line).