Direct Numerical Simulation of Microscale Rheology and Multiphase Flow in Porous Media Jonathan J.L. Higdon, Department of Chemical and Biomolecular Engineering Multiphase fluid flows such as the concentrated emulsion pictured here exhibit a wide range of complex behavior. This includes shear induced phase separation (as in the two drop sizes shown here), order-disorder transitions, shear banding and non-Newtonian rheology. We are developing a set of novel computational algorithms based on a spectral boundary element approach which will allow researchers to make theoretical predictions of the behavior of these complex fluids. The successful development of this computational toolbox will provide a valuable resource for industrial researchers to find optimal choices of material properties such as the fluid viscosities, droplet concentrations and surfactants , as well as optimal flow conditions for efficient processing of multiphase fluid flows.