فرخنده مظفری

In perturbed hard-sphere-chain equation of state, a system of hard-sphere-chain equations is taken in to account as the reference system and an attraction term is added as the perturbation. Generally, in this equation of state two temperature-dependent parameters; the attractive forces between non-bonded segments and the effective van der Waals covolume and there is another parameter representing the number of segment per chain perturbed hard-sphere-chain equation of state which obtainable by fitting experimental data. by Using the principle corresponding states and knowing the two parameters, enthalpy evaporation and density at the triple point which are empirically obtainable. In this work, it is shown that it is possible to obtain the temperature-dependent parameters of the EOS with sufficient accuracy in the equation of state with two parameters as scale constants, with no requirement of inter-molecular potential. We have tested the proposed equation of state for a large number of fluids including a number of monoatomic, diatomics, polyatomic inorganic molecules, saturated hydrocarbons up to n-C8H18 and some compounds of refrigerants are examined.The agreement with experiment is quite good.