부산대학교 도서관

This progress report covers research carried out during the period September 15, 1987--September 15, 1990. The main emphasis of the work was on dense fluid mixtures, although in some cases work had to be done on pure fluids before we could study mixtures in a meaningful way. A summary of our results is given. (1) An algorithm was developed and used to calculate the viscosity and thermal conductivity of continuous, or polydisperse mixtures with various distributions (e.g. linear, several gaussian distributions including unsymmetric, etc.) using nonequilibrium molecular dynamics (NEMD). (2) A method was developed to calculate the thermal conductivity of nonspherical (rigid) molecules using NEMD. (3) The NEMD method for thermal conductivity of nonspherical molecules was used to have a careful look at the contributions due to internal rotational degrees of freedom in linear compounds such as chlorine, nitrogen, etc. (4) It has long been speculated that polar fluids exhibit heat induced birefringence, i.e., the molecules will tend to align themselves along the direction of an external heat field. Using nonequilibrium molecular dynamics we were able to conclusively confirm this. (5) We completed a preliminary study of the viscosity of homonuclear diatomics and their mixtures (e.g. N{sub 2}, Cl{sub 2}, etc.). (6) We completed a study of the various flexibility (vibrational) effects, such as bond bending, bond stretching etc., on linear and nonlinear model triatomics. To examine these effects in our preliminary study, we looked at the pressure second virial coefficients.