Singularity image method for electrical impedance tomography of bubbly flows (2003)
Huang, Cunkui, Lee, Jinhee, Schultz, William W., Ceccio, Steven L
A singularity image method is applied to the electrical impedance tomography of gas–liquid flows in a two-dimensional circular domain. Algorithms that use analytic complex functions, dipoles and...
Modelling and analysis of metal transfer in gas metal arc welding (2003)
Wang, F, Hou, W K, Hu, S. Jack, Kannatey-Asibu, Elijah, Schultz, William W., Wang, P. C.
A numerical model combining the methods of enthalpy, effective-viscosity and volume-of-fluid is developed to simulate the metal transfer process in gas metal arc welding. The model describes not only...
IEEE November 6 - 9, 2002, Boston, MA (2002)
William Oakes, John Duffy, Thomas Jacobius, Panos Linos, Susan Lord, William W. Schultz
Service learning is a pedagogy that integrates academic learning with community-based work. Service learning has been widely adopted within higher education nationally in many disciplines and offers...
Linear and nonlinear gravity-capillary water waves with a soluble surfactant (2001)
Schultz, William W., Lapham, G. S., Dowling, David R.
Naturally occurring soluble-surfactant slicks influence the properties of water waves. This paper describes results from wave tank experiments involving a soluble surfactant, and linear and nonlinear...
In situ force-balance tensiometry (1999)
Dowling, David R., Schultz, William W., Lapham, G. S.
Although a fundamental physical parameter, surface tension is difficult to measure. Common tensiometry inaccuracy comes from failure to control air–liquid–solid contact conditions, or account...
Numerical Study Of A Contaminated Surface Deformation By A Vortex Pair (1999)
Shiyuan Eric Gou, William W. Schultz, Gretar Tryggvason
Interaction between a vortex pair and a contaminated free surface is studied numerically using a front-tracking method. The results are compared to earlier results for #at or clean surfaces. The...
Unsteady Ripple Generation on Steep Gravity-Capillary Waves (1999)
Lei Jiang, Huan-jay Lin, William W. Schultz, Marc Perlin
Parasitic ripple generation on short gravity waves (5 cm to 10 cm wavelengths) is examined...
One-Dimensional Dynamic Model Of A Paper Forming Process (1999)
Paul F. Turnbull, William W. Schultz, Noel C. Perkins, Paul D. Beuther
A one dimensional, unsteady model of the wet end of a paper forming process is derived from fundamental conservation laws. The stock is approximated as an inviscid #uid and the wire as an axially...
Three-Dimensional Desingularized Boundary Integral Methods for Potential Problems. (1998)
Cao, Yusong, Schultz, William W., Beck, Robert F.
The concept of desingularization in three-dimensional boundary integral computations is reexamined. The boundary integral equation is desingularized by moving the singular points away from the...
Nonisothermal model of glass fiber drawing stability (1996)
Schultz, William W., Gupta, Gyanesh K., Lu, Xiaoyong, Arruda, Ellen M.
Draw resonance is caused by a constant speed winder that leads to non-constant axial forces (Schultz, 1984). The well studied isothermal Newtonian fiber drawing predicts very modest critical draw...
Numerical computations of two-dimensional solitary waves generated by moving disturbances (1993)
Cao, Yusong, Beck, Robert F., Schultz, William W.
Two-dimensional solitary waves generated by disturbances moving near the critical speed in shallow water are computed by a time-stepping procedure combined with a desingularized boundary integral...
Li, L., Schultz, William W., Merte, Herman
The velocity potential around two spheres moving perpendicularly to the line joining their centers is given by a series of spherical harmonics. The appropriateness of the truncation is evaluated by...
An efficient finite element method for treating singularities in Laplace's equation (1991)
Olson, Lorraine G., Georgiou, Georgios C., Schultz, William W.
We present a new finite element method for solving partial differential equations with singularities caused by abrupt changes in boundary conditions or sudden changes in boundary shape. Terms from...
Three-dimensional desingularized boundary integral methods for potential problems (1991)
Cao, Yusong, Schultz, William W., Beck, Robert F.
The concept of desingularization in three-dimensional boundary integral computations is re-examined. The boundary integral equation is desingularized by moving the singular points away from the...
Spectral method solution of the Stokes equations on nonstaggered grids (1991)
Schumack, Mark R., Schultz, William W., Boyd, John P.
The Stokes equations are solved using spectral methods with staggered and nonstaggered grids. Numerous ways to avoid the problem of spurious pressure modes are presented, including new techniques...
Singular finite elements for the sudden-expansion and the die-swell problems (1990)
Georgiou, Georgios C., Schultz, William W., Olson, Lorraine G.
The singular finite element method is used to solve the sudden-expansion and the die-swell problems in order to improve the accuracy of the solution in the vicinity of the singularity and to speed up...
A singular finite element for Stokes flow: The stick–slip problem (1989)
Georgiou, Georgios C., Olson, Lorraine G., Schultz, William W., Sagan, Susan
Abrupt changes in boundary conditions in viscous flow problems give rise to stress singularities. Ordinary finite element methods account effectively for the global solution but perform poorly near...
Solution of potential problems using an overdetermined complex boundary integral method (1989)
Schultz, William W., Hong, S. W.
The advantages of solving potential problems using an overdetermined boundary integral element method are examined. Representing a 2-dimensional potential solution by an analytic complex function...
Stability of fluid in a rectangular enclosure by spectral method (1989)
Lee, N. Y., Schultz, William W., Boyd, John P.
The hydrodynamic stability of Rayleigh convection in a rectangular cavity is studied numerically. The calculation assumes that the Boussinesq fluid motion is two-dimensional. The characteristic value...
Chebyshev pseudospectral method of viscous flows with corner singularities (1989)
Schultz, William W., Lee, N. Y., Boyd, John P.
Chebyshev pseudospectral solutions of the biharmonic equation governing two-dimensional Stokes flow within a driven cavity converge poorly in the presence of corner singularities. Subtracting the...