NF ISO 20765-1
Natural gas - Calculation of thermodynamic properties - Part 1 : gas phase properties used in transmission and distribution applications
This part of ISO 20765 specifies a method of calculation for the volumetric and caloric properties of natural gases, natural gases containing synthetic admixture and similar mixtures, at conditions where the mixture can exist only as a gas.The method is applicable to pipeline-quality gases within the ranges of pressure and temperature at which transmission and distribution operations normally take place. For volumetric properties (compression factor and density), the uncertainty of calculation is about ± 0,1 % (95 % confidence interval). For caloric properties (for example enthalpy, heat capacity, Joule-Thomson coefficient, speed of sound), the uncertainty of calculation is usually greater.
This part of ISO 20765 specifies a method of calculation for the volumetric and caloric properties of natural gases, natural gases containing synthetic admixture and similar mixtures, at conditions where the mixture can exist only as a gas.
The method is applicable to pipeline-quality gases within the ranges of pressure and temperature at which transmission and distribution operations normally take place. For volumetric properties (compression factor and density), the uncertainty of calculation is about ± 0,1 % (95 % confidence interval). For caloric properties (for example enthalpy, heat capacity, Joule-Thomson coefficient, speed of sound), the uncertainty of calculation is usually greater.
This part of ISO 20765 specifies a method of calculation for the volumetric and caloric properties of natural gases, natural gases containing synthetic admixture and similar mixtures, at conditions where the mixture can exist only as a gas. The method is applicable to pipeline-quality gases within the ranges of pressure and temperature at which transmission and distribution operations normally take place. For volumetric properties (compression factor and density), the uncertainty of calculation is about ± 0,1 % (95 % confidence interval). For caloric properties (for example enthalpy, heat capacity, Joule-Thomson coefficient, speed of sound), the uncertainty of calculation is usually greater.
- Avant-proposiv
- Introductionv
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1 Domaine d'application1
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2 Références normatives1
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3 Termes et définitions1
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4 Base thermodynamique de la méthode2
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5 Méthode de calcul9
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6 Plages d'application11
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7 Incertitude12
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8 Consignation des résultats dans un rapport15
- Annexe A (normative) Symboles et unités17
- Annexe B (normative) Énergie libre de Helmholtz du gaz parfait21
- Annexe C (normative) Équation de l'énergie libre de Helmholtz24
- Annexe D (normative) Documentation détaillée de l'équation d'état26
- Annexe E (informative) Attribution des constituants à l'état de traces32
- Annexe F (informative) Application de la méthode34
- Annexe G (informative) Exemples37
- Bibliographie44
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