most reservoir fluids contain heavy paraffinic compounds that may precipitate as a solid or solid like material called wax if the fluid is cooled down. wax precipitation is a phenomenon of considerable importance in oil industry. an increase in aggregation results in enhanced oil viscosity. this however causes significant negative effects on production, transportation and processing of crude oi...

The second virial coefficients are given as a spherical-core contribution plus a series of nonspherical perturbation terms. A revised analysis is given of the effect of long-range nonspherical terms in the intermolecular potential on the second virial coefficient given by a preferred HFDIDl spherical core treatment of the integration for small intermolecular distances. This effect is consid...

an interaction potential at different orientation for the ch4 and co2 complex was derived at theb3lyp level of theory and 6-31+g* basis sets. the potential energy surface was computed on somemolecular geometries. the complete basis set limit of the interaction energies were fitted to wellknownanalytical functions. to determine the second virial coefficients b, u(r) is used to obtain themodel’s ...

a revised analysis of the effect of long-range nonspherical terms in the intermolecular potential on the second virial coefficient is presented with a preferred hartree-fock-dispersion functional (hfd-c) spherical core treatment of the integrations for small intermolecular distances. a set of modified numerical tables for the accurate calculation of the nonspherical contribution to the second v...