Sound velocity and isentropic exponents for gases with different acentric factors by using the Redlich-Kwong-Soave equation of state

Kouremenos, DA; Antonopoulos, KA

dc.contributor.author	Kouremenos, DA	en
dc.contributor.author	Antonopoulos, KA	en
dc.date.accessioned	2014-03-01T01:06:59Z
dc.date.available	2014-03-01T01:06:59Z
dc.date.issued	1987	en
dc.identifier.issn	0001-5970	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/9720
dc.subject	Equation of State	en
dc.subject.classification	Mechanics	en
dc.subject.other	GAS DYNAMICS - Mathematical Models	en
dc.subject.other	EQUILIBRIUM	en
dc.subject.other	IDEAL GAS	en
dc.subject.other	ISENTROPY	en
dc.subject.other	EQUATIONS OF STATE	en
dc.title	Sound velocity and isentropic exponents for gases with different acentric factors by using the Redlich-Kwong-Soave equation of state	en
heal.type	journalArticle	en
heal.identifier.primary	10.1007/BF01184292	en
heal.identifier.secondary	http://dx.doi.org/10.1007/BF01184292	en
heal.language	English	en
heal.publicationDate	1987	en
heal.abstract	In previous publications, three real gas isentropic exponents kpv, kTv, kpT have been introduced, which when used instead of the classical isentropic exponent k=cp/cv in the ideal gas isentropic change equations, the latter may be applied with great accuracy to real gases. The first of the exponents may also be employed for calculating the real gas sound velocity as α=(kpvpv)1/2. The exact values of the sound velocity α and of the three isentropic exponents kpv, kTv, kpT of a real gas may be calculated only if the exact thermal and caloric equations of state of this real gas are available. For most real gases, however, such equations are not available. In the present work, correlations are presented for calculating quantities α, kpv, kTv, kpT for all real gases, in terms of the acentric factor which characterises their deviation from the ideal gas. The correlations, which are based on the Redlich-Kwong-Soave generalized equation of state, provide the above quantities in a generalized reduced form in terms of the reduced temperature, of the reduced volume and of the compressibility factor, i.e. independently of any gas properties except for the acentric factor. Therefore, it becomes possible to plot the generalized sound velocity and isentropic exponents on the generalized compressibility chart (Nelson-Obert diagram) for various values of the acentric factor. Comparisons with exact values in the case of real air, calculated by use of exact thermal and caloric equations, show that the accuracy of the correlations developed is satisfactory. © 1987 Springer-Verlag.	en
heal.publisher	Springer-Verlag	en
heal.journalName	Acta Mechanica	en
dc.identifier.doi	10.1007/BF01184292	en
dc.identifier.isi	ISI:A1987J094800012	en
dc.identifier.volume	66	en
dc.identifier.issue	1-4	en
dc.identifier.spage	177	en
dc.identifier.epage	189	en