- Fluid dynamics,
- Fluids -- Thermal properties,
- Fluid dynamics -- Mathematical models
An improved self-consistent effective binary diffusion approximation for multicomponent diffusion was recently described . Here we develop an analogous self-consistent effective binary interaction (SCEBI) approximation for simplifying multifluid dynamical descriptions in which each fluid is strongly coupled to the other fluids by pairwise frictional forces. The net drag force on each fluid is the summation of the drag forces due to each of the other fluids. This summation is approximated by a single term proportional to the velocity of the fluid in question relative to an appropriately weighted average velocity. This approximation permits an explicit numerical solution for the fluid velocities even when the drag terms are evaluated at the advanced time level to avoid explicit stability restrictions on the time step.