Steam, water properties

Transport Properties. Viscosity, themial conductivity, the speed of sound, and various combinations of these with other properties are called steam transport properties, which are important in engineering calculations. The speed of sound (Fig. 6) is important to choking phenomena, where the flow of steam is no longer simply related to the difference in pressure. Thermal conductivity (Fig. 7) is important to the design of heat-transfer apparatus (see HeaT-EXCHANGETECHNOLOGy). The viscosity, ie, the resistance to flow under pressure, is shown in Figure 8. The sharp declines evident in each of these properties occur at the transition from Hquid to gas phase, ie, from water to steam. The surface tension between water and steam is shown in Figure 9. 

Water properties can be found from tables, such as the VDl-Wasser-dampftafeln The NBS/NRC Steam Tables the ASHRAE and CIBSE Guides or Thermodynamic and Transport Properties of Fluids by Mayhew and Rodgers. First we dimension d, and now Eq. (4.65) is... 

Vessel blowdown. The previously mentioned relationships for the critical flow rate of a steam-water mixture can be employed with the conservation of mass and energy for a vessel of fixed volume to determine its time-dependent blowdown properties. The range of problems associated with coolant decompression in water-cooled reactors is quite broad. The types of hypothetical (some are even incredible) reactor accidents may be... 

The International Association for the Properties of Water and Steam (IAPWS) provides internationally accepted values and formulations for the properties of light and heavy steam, water, and selected aqueous solutions for scientific and industrial applications. IAPWS Releases and Guidelines can be obtained online at http //www.iapws.org. 

Valyashko VM. Phase equilibria and solution properties of aqueous systems at high temperatures and pressures. Proceedings of the 13th International Conference on the Properties of Water and Steam. Steam, Water, and Hydrothermal Systems Physics and Chemistry Meeting the Needs of Industry, Toronto, Canada, Sept 12-16, 1999. Ottawa, Canada NRC Research Press, 2000, pp. 727-735. 

Related Calculations. These equations are presented in Dickey, D.S., Practical Formulas Calculate Water Properties, Parts 1 and 2, Chem. Eng., Sept. 1991, pp. 207, 208 and November 1991, pp. 235, 236. That author developed the equations via regression analysis of the properties of saturated steam as presented in Perry s Chemical Engineers Handbook, 6th ed., McGraw-Hill. The maximum error (compared to tabulated values) and sample standard deviation of the correlations are as follows ... 

Hill, P.G. MacMillan, R.D.C. Water and steam—their properties and current industrial applications. Proceedings of the 9th International Conference on the Properties of Steam. Straub, J., Scheffler, K., Eds. Pergamon Press New York, 1980 105, 344. 

Total internal energy of steam + water in the tank 194.932x313.0 + 14.476x2475.9 = 9.686xl04 kJ Properties of steam entering, 90% quality... 

There is a simple relationship between the thermodynamic properties of a two-phase mixture (e.g., a mixture of water and steam), the properties of the individual phases, and the mass distribution between the phases. If 0 is any intensive property, such as internal energy per unit mass or volume per unit mass, its value in an equilibrium two-phase mixture is... 

A "solvent is a relatively safe fluid whose properties are close to those of the process fluid. Solvent testing is sometimes used as an alternative to steam-water testing (Sec. 11.7). The purpose of solvent testing... 

Besides, there are certain limitations on temperature conditions for some steels (for example, stability of mechanical properties of 2V4CrlMo steel can only be guaranteed at temperature not exceeding 520°C). It should be also noted that practically all of the above steels have adequate corrosion resistance in pure sodium and all corrosion problems take place on the steam-water side. So it is seen that choosing tube material is rather complicated problem. 

Wagner, W. and Kretzschmar, H.J. (2008) International Steam Tables - Properties of Water and Steam Based on the Industrial Formulation of the IAPWS-IF97, Springer, Berlin. 

Wooley, H. W., 1980, Thermodynamic properties for H2O in the ideal gas state, in Water and Steam - Their Properties and Current Industrial Applications. Proceedings of the 9th International Conference on the Properties of Steam, J. Straub and K. Scheffler, eds., Oxford Pergamon, pp. 166-80. 

Software Properties of Steam Water(1990), American Society of Mechanical Engineers... 

It would be highly desirable for reasons of thermodynamic consistency and to avoid energy discontinuities to use just one thermodynamic model representing the properties of all parts of a process but no consistent thermodynamic model can with a sufficient accuracy calculate the thermodynamic properties of all relevant syngas mixtures. This is not only due to the absence of adequate mixing rules for mixtures of steam/water and other compounds, but also that water has... 

A practical solution is therefore to calculate thermodynamic properties by combining the steam/water model from the Steam Tables with the properties of the other components as calculated from the SRK equation of state. 

Corti, H.R. Trevani, L.N. and Anderko, A. (2004) Transport properties in high temperature and pressure ionic solutions. In D. Pahner, R. Fernandez Prini and A. Harvey (eds), Steam, Water and Hydrothermal Solutions Physical Chemistry of Aqueous... 

Parry, W. T. 2009. ASME International Steam Tables for Industrial Use, 2nd ed. New York ASME (American Society of Mechanical Engineers). A standard set of thermodynamic and transport properties for water and steam. Based on the International Association for the Properties of Water and Steam s Formulation 1997. This is a complanentary reference to the NIST/ASME Steam Properties Database http //www.nisLgov/srd/nistl0.cfm (accessed November 10, 2010) Based upon the new International Association for the Properties of Water and Steam (lAPWS) 1995 formulation for general and scientific use for the thermodynamic properties of water, this updated version provides water properties from the international standards over a wide range of conditions. 

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