Search results
Results from the WOW.Com Content Network
In thermodynamics, a critical point (or critical state) is the end point of a phase equilibrium curve. One example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a liquid and its vapor can coexist.
The Ambrose method was published by Douglas Ambrose in 1978 and 1979. It can be used to estimate critical temperature, critical pressure, and critical volume. In addition to the molecular structure, it requires normal boiling point for estimating critical temperature and molecular weight for estimating critical pressure. [9] [10]
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 ...
The Lee–Kesler method [1] allows the estimation of the saturated vapor pressure at a given temperature for all components for which the critical pressure P c, the critical temperature T c, and the acentric factor ω are known.
Once and are experimentally determined for a given substance, the van der Waals equation can be used to predict the boiling point at any given pressure, the critical point (defined by pressure and temperature values, , such that the substance cannot be liquefied either when > no matter how low the temperature, or when > no matter how high the ...
The Lydersen method [1] is a group contribution method for the estimation of critical properties temperature (T c), pressure (P c) and volume (V c).The Lydersen method is the prototype for and ancestor of many new models like Joback, [2] Klincewicz, [3] Ambrose, [4] Gani-Constantinou [5] and others.
The critical point remains a point on the surface even on a 3D phase diagram. An orthographic projection of the 3D p–v–T graph showing pressure and temperature as the vertical and horizontal axes collapses the 3D plot into the standard 2D pressure–temperature diagram. When this is done, the solid–vapor, solid–liquid, and liquid ...
The acentric factor ω is a conceptual number introduced by Kenneth Pitzer in 1955, proven to be useful in the description of fluids. [1] It has become a standard for the phase characterization of single and pure components, along with other state description parameters such as molecular weight, critical temperature, critical pressure, and critical volume (or critical compressibility).