Showing papers by "William J. Rider published in 1995"

Accurate solution algorithms for incompressible multiphase flows

Abstract: A number of advances in modeling multiphase incompressible flow are described. These advances include high-order Godunov projection methods, piecewise linear interface reconstruction and tracking and the continuum surface force model. Examples are given.

A comparison of interface tracking methods

Abstract: In this Paper we provide a direct comparison of several important algorithms designed to track fluid interfaces In the process we propose improved criteria by which these methods are to be judged We compare and contrast the behavior of the following interface tracking methods: high order monotone capturing schemes, level set methods, volume-of-fluid (VOF) methods, and particle-based (particle-in-cell, or PIC) methods We compare these methods by first applying a set of standard test problems, then by applying a new set of enhanced problems designed to expose the limitations and weaknesses of each method We find that the properties of these methods are not adequately assessed until they axe tested with flows having spatial and temporal vorticity gradients Our results indicate that the particle-based methods are easily the most accurate of those tested Their practical use, however, is often hampered by their memory and CPU requirements Particle-based methods employing particles only along interfaces also have difficulty dealing with gross topology changes Full PIC methods, on the other hand, do not in general have topology restrictions Following the particle-based methods are VOF volume tracking methods, which are reasonably accurate, physically based, robust, low in cost, and relatively easy to implement Recent enhancements to the VOF methods using multidimensional interface reconstruction and improved advection provide excellent results on a wide range of test problems