A correlation for heat of vaporization of pure compounds

Abstract

Twenty-seven selected equations were tested on 162 compounds with 1958 calorimetric data for their abilities to reflect the temperature influence on the heat of vaporization of pure compounds. A new equation is recommended (overall percent deviation 0.27% and percent deviation 0.59% above 0.9T r ).

Vaporization Enthalpy of Pure Refrigerants: Comparative Study of Eighteen Correlations

“…Once the inputs were introduced, 7 correlations included 2 adjustable coefficients, and the other 11 correlations included 3 adjustable coefficients. Some of these correlations are classical expressions and have been considered in previous studies, − ,, but others have been proposed recently or have been slightly modified or extended for this study.…”

“…A plethora of correlations have been proposed in order to fit the enthalpy of vaporization of pure fluids as a function of the temperature. [10][11][12][13][14] Some of them include coefficients that must be calculated for each substance, [15][16][17][18][19][20][21][22][23][24] or the value of the enthalpy at a given temperature. [25][26][27][28][29][30][31][32][33][34] The choice of a specific equation depends on several factors, mainly, the available number of experimental data, the temperature range over which one wants to apply the correlation, and the set of substances chosen for testing the equation.…”

“…Nevertheless, the Park study does not consider some other recent interesting proposals, such as those of Chen et al, 28 Roma ´n et al, 31 Velasco et al, 32 and Al-Shorachi and Hashim, 33 and that used in the DIPPR database, 37 which is due to the work of Chueh and Swanson. 38 Also recently, Jovanovic and Grozdanic 24 have tested 27 correlations, including a new one proposed by them, using 1958 data for 162 compounds. The new equation, with 4 adjustable coefficients, gave an overall percentage deviation of 0.27% for the whole temperature range for 157 fluids, and of 0.59% for temperatures above 0.9 times the critical temperature (only for 19 fluids).…”

“…A plethora of correlations have been proposed in order to fit the enthalpy of vaporization of pure fluids as a function of the temperature. − Some of them include coefficients that must be calculated for each substance, − or the value of the enthalpy at a given temperature. − …”

“…Also recently, Jovanovic and Grozdanic have tested 27 correlations, including a new one proposed by them, using 1958 data for 162 compounds. The new equation, with 4 adjustable coefficients, gave an overall percentage deviation of 0.27% for the whole temperature range for 157 fluids, and of 0.59% for temperatures above 0.9 times the critical temperature (only for 19 fluids).…”