Reduced properties are also used to define the Peng–Robinson equation of state, a model designed to provide reasonable accuracy near the critical point.[2] They are also used to critical exponents, which describe the behaviour of physical quantities near continuous phase transitions.[3]
The reduced pressure is defined as its actual pressure divided by its critical pressure:[1]
Reduced temperatureedit
The reduced temperature of a fluid is its actual temperature, divided by its critical temperature:[1]
where the actual temperature and critical temperature are expressed in absolute temperature scales (either Kelvin or Rankine). Both the reduced temperature and the reduced pressure are often used in thermodynamical formulas like the Peng–Robinson equation of state.
Reduced specific volumeedit
The reduced specific volume (or "pseudo-reduced specific volume") of a fluid is computed from the ideal gas law at the substance's critical pressure and temperature:[1]
This property is useful when the specific volume and either temperature or pressure are known, in which case the missing third property can be computed directly.
^ abcdCengel, Yunus A.; Boles, Michael A. (2002). Thermodynamics: an engineering approach. Boston: McGraw-Hill. pp. 91–93. ISBN0-07-121688-X.
^Peng, DY & Robinson, DB (1976). "A New Two-Constant Equation of State". Industrial and Engineering Chemistry: Fundamentals. 15: 59–64. doi:10.1021/i160057a011. S2CID 98225845.
^Hagen Kleinert and Verena Schulte-Frohlinde, Critical Properties of φ4-Theories, pp.8, World Scientific (Singapore, 2001); ISBN981-02-4658-7(Read online at [1])
April 11, 2024
reduced, properties, thermodynamics, reduced, properties, fluid, state, variables, scaled, fluid, state, properties, critical, point, these, dimensionless, thermodynamic, coordinates, taken, together, with, substance, compressibility, factor, provide, basis, s. In thermodynamics the reduced properties of a fluid are a set of state variables scaled by the fluid s state properties at its critical point These dimensionless thermodynamic coordinates taken together with a substance s compressibility factor provide the basis for the simplest form of the theorem of corresponding states 1 Reduced properties are also used to define the Peng Robinson equation of state a model designed to provide reasonable accuracy near the critical point 2 They are also used to critical exponents which describe the behaviour of physical quantities near continuous phase transitions 3 Contents 1 Reduced pressure 2 Reduced temperature 3 Reduced specific volume 4 See also 5 ReferencesReduced pressure editThe reduced pressure is defined as its actual pressure p displaystyle p nbsp divided by its critical pressure pc displaystyle p rm c nbsp 1 pr ppc displaystyle p rm r p over p rm c nbsp Reduced temperature editThe reduced temperature of a fluid is its actual temperature divided by its critical temperature 1 Tr TTc displaystyle T rm r T over T rm c nbsp where the actual temperature and critical temperature are expressed in absolute temperature scales either Kelvin or Rankine Both the reduced temperature and the reduced pressure are often used in thermodynamical formulas like the Peng Robinson equation of state Reduced specific volume editThe reduced specific volume or pseudo reduced specific volume of a fluid is computed from the ideal gas law at the substance s critical pressure and temperature 1 vr vpcRTc displaystyle v rm r frac vp rm c RT rm c nbsp This property is useful when the specific volume and either temperature or pressure are known in which case the missing third property can be computed directly See also editDeparture functionReferences edit a b c d Cengel Yunus A Boles Michael A 2002 Thermodynamics an engineering approach Boston McGraw Hill pp 91 93 ISBN 0 07 121688 X Peng DY amp Robinson DB 1976 A New Two Constant Equation of State Industrial and Engineering Chemistry Fundamentals 15 59 64 doi 10 1021 i160057a011 S2CID 98225845 Hagen Kleinert and Verena Schulte Frohlinde Critical Properties of f4 Theories pp 8 World Scientific Singapore 2001 ISBN 981 02 4658 7 Read online at 1 Retrieved from https en wikipedia org w index php title Reduced properties amp oldid 1150480021, wikipedia, wiki, book, books, library,
