(741a) Avoiding Artifacts in Non-Cubic Equations of State

Artifacts are mathematical solutions to pressure-volume-temperature equations of state (EOSs) that have no physical meaning. These roots cause confusion and failure when applying EOSs, especially when extending to mixtures. These failures can undermine process simulations or flow field simulations. Artifacts can be avoided by restricting consideration to cubic EOSs, but that restriction limits the accuracy that can be achieved. This presentation provides a review of artifacts that appear in common equations of state and how they can be avoided, even for non-cubic EOSs. Notably, focusing greater attention on the physical basis of each term in the EOS avoids the introduction of artifacts while bolstering insights about regions where experimental measurements are difficult or impossible. In this way, molecular simulations of unstable or inhomogeneous systems can be incorporated with precise experimental measurements to approach reference quality accuracy for all properties while avoiding artifacts except at conditions extremely outside the fluid range.