Cubic equations of state(EOSs) are simple and easy at calculation. One way of improving the accuracy of a cubic EOS is through the modification of temperature-dependent energy parameter by using alpha-function.The ind...Cubic equations of state(EOSs) are simple and easy at calculation. One way of improving the accuracy of a cubic EOS is through the modification of temperature-dependent energy parameter by using alpha-function.The industrial applications of natural gas are very wide and as a result, prediction of thermodynamic properties and phase behavior of natural gas is an important part of design for such processes. In this work we develop a newα-function for the Peng-Robinson(PR) EOS with the parameters optimized especially for natural gas components.The parameters are generalized as a linear function of acentric factor. The results are compared to the predictions from original PR EOS and other α-functions in literature. It is shown that the new α-function presents a good accuracy with the average deviation of 1.42% for natural gas components.展开更多
Viscosities of uranium solutions in H2O and 3 mol/L HNO3 medium were measured by Ubbelhode flow vis-cometer in the concentration range of 0.5%3.0% from 10 篊 to 30 篊 at 5 篊 interval. Viscosity data were interpreted ...Viscosities of uranium solutions in H2O and 3 mol/L HNO3 medium were measured by Ubbelhode flow vis-cometer in the concentration range of 0.5%3.0% from 10 篊 to 30 篊 at 5 篊 interval. Viscosity data were interpreted in terms of an empirical equation; h =aoexp(boM+coM2). Values of coefficients ao, bo and co were calculated for all the three systems studied. Flow activation energies and thermodynamic parameters were also evaluated.展开更多
The simplest equation of state that can be applied to calculate the thermodynamic properties of gases is the virial equation with the second coefficient B. The probability of applying the one-coefficient equation Z = ...The simplest equation of state that can be applied to calculate the thermodynamic properties of gases is the virial equation with the second coefficient B. The probability of applying the one-coefficient equation Z = exp(A/V) for the calculation of compressibility factor at critical temperature of gases and gas mixtures is investigated. It was verified that the one-coefficient equation of state can be applied to calculated the thermodynamic properties for both normal and strongly polar gases and gas mixtures.展开更多
文摘Cubic equations of state(EOSs) are simple and easy at calculation. One way of improving the accuracy of a cubic EOS is through the modification of temperature-dependent energy parameter by using alpha-function.The industrial applications of natural gas are very wide and as a result, prediction of thermodynamic properties and phase behavior of natural gas is an important part of design for such processes. In this work we develop a newα-function for the Peng-Robinson(PR) EOS with the parameters optimized especially for natural gas components.The parameters are generalized as a linear function of acentric factor. The results are compared to the predictions from original PR EOS and other α-functions in literature. It is shown that the new α-function presents a good accuracy with the average deviation of 1.42% for natural gas components.
文摘Viscosities of uranium solutions in H2O and 3 mol/L HNO3 medium were measured by Ubbelhode flow vis-cometer in the concentration range of 0.5%3.0% from 10 篊 to 30 篊 at 5 篊 interval. Viscosity data were interpreted in terms of an empirical equation; h =aoexp(boM+coM2). Values of coefficients ao, bo and co were calculated for all the three systems studied. Flow activation energies and thermodynamic parameters were also evaluated.
文摘The simplest equation of state that can be applied to calculate the thermodynamic properties of gases is the virial equation with the second coefficient B. The probability of applying the one-coefficient equation Z = exp(A/V) for the calculation of compressibility factor at critical temperature of gases and gas mixtures is investigated. It was verified that the one-coefficient equation of state can be applied to calculated the thermodynamic properties for both normal and strongly polar gases and gas mixtures.
