Industrial Applied Mathematics

People

  • Richard Braun, Professor
    Nonlinear BVPs and free boundary problems in fluid mechanics and materials science

  • Fioralba Cakoni, Professor
    Boundary integral equations and coupling BEM-FEM. Applications in electromagnetic and elastic scattering problems

  • David Colton, UNIDEL Professor
     Scattering and inverse scattering

  • L. Pamela Cook, Professor
     Complex fluids, viscoelastic fluids: flows and modeling; transonic aerodynamics

  • Tobin Driscoll, Professor
     High-order and spectral methods for differential equations;  radial basis functions;  numerical conformal mapping

  • David Edwards, Professor
     Asymptotic and perturbation methods in biochemical, chemical engineering, and viscoelastic systems

  • George C. Hsiao, Carl Rees Professor of Mathematics
      Boundary integral equations, finite element methods. Applications in elasticity. Signal and image processing, computational optics, and inverse problems

  • Peter Monk, UNIDEL Professor
     Finite element methods, applications in computational electromagnetism and inverse problems

  • David Olagunju, Professor
     Viscoelastic flows, stability, bifurcations, dynamical systems and combustion

  • John Pelesko, Professor and Chair
     Mathematical modeling of real world micro- and nanoscale devices. Problems arising in an industrial setting that involve continuum mechanicss

  • Rakesh, Professor
     Scattering and inverse problems

  • Louis Rossi, Professor
     Neural networks, vortex methods, flow in porous media and fluid mechanics

  • Gilberto Schleiniger, Associate Professor
     Fluid flow: viscoelastic and transonic flows; mathematical finance

Research

There are a wide range of problems being solved in collaboration with industry and national labs.  Research ranges from basic numerical analysis (finite element, boundary element and finite difference convergence theory) and fast methods (multigrid) to applications in materials science (foam evolution, phase transformations in crystalline alloys, approximation of microstructure, visco-elastic phenomena) and electromagnetism (scattering, inverse scattering and ferromagentism).  Graduate students are welcome!

Seminars

A variety of application areas and mathematical methods are featured in the Applied Mathematics seminar series. A weekly seminar calendar gives up-to-date information on this and other seminars in the department

Graduate Studies

Students wishing to study applied mathematics usually enroll in the Applied Mathematics graduate program (see The Graduate Program web pages for more details). There are a number of courses for students interested in this area as well as topics courses. For example

Funding

Besides the usual university and departmental funding for TAs and fellows some students are also supported directly by companies

Many of the projects listed here have been at least partially supported by the National Science Foundation under grant numbers 9722854, 9631287 and 0322583. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Computing Resources

The department operates several computers in support of research computing. All faculty and graduate students involved with scientific computing have personal workstations.

Completed Projects

Mathematical Problems in Industry Workshop 2004
Richard Braun, braun@math.udel.edu
Philip Broadbridge
Pam Cook
Tobin Driscoll
David Edwards, edwards@math.udel.edu
John Pelesko
Louis Rossi
Gilberto Schleiniger
Don Schwendeman, Rensselaer Polytechnic Institute
Bogdan Vernescu, Worcester Polytechnic Institute
Joseph Fehribach, Worcester Polytechnic Institute
Tom Witelski, Duke University
Burt Tilley, Olin College

The Department of Mathematical Sciences hosted the 20th annual Mathematical Problems in Industry workshop, June 21-25, 2004.

DuPont
Capillary viscometry for polymer processing
Bryan Wood, U of Delaware
Pam Cook (PI), cook@math.udel.edu
Gilberto Schleiniger (PI), schleini@math.udel.edu
Emeka Nwankwo, DuPont

Bryan Wood completed his PhD working on the mathematical modeling of the flow of a polymer solution in a small tube; this work is expected to help improve the efficiency of some of DuPont's polymer processes. He was supported by the GIG at U of Delaware and by support in kind from DuPont. The project is being supervised by Pam Cook and Gilberto Schleiniger; they were supported by an ATE grant from DuPont.

AstroPower
Crystal Growth on a Substrate
Mikhail Khenner, U of Delaware
Richard Braun (PI), braun@math.udel.edu
Michael Mauk, AstroPower

Theory is being developed for crystal growth of a not-necessarily thin film on a substrate with a mask. The fully nonlinear surface geometry was taken into account with a geometric growth model including surface diffusion and condensation from the vapor; the anistropic case was studied as well. The anisotropic case is now being considered. This started out as a follow-on project from the MPI 1999 meeting held at UD. Rich is partially supported by, and Mikhail was fully supported by NSF GIG DMS-9631287 during his stay at UD. The paper that appeared from this project is "A Model for Anisotropic Epitaxial Lateral Overgrowth," M. Khenner, R.J. Braun and M.G. Mauk, J. Crystal Growth 241, (2002) 330-346.

Air Force
On the Mathematical Basis of the Linear Sampling Method
David Colton (PI), colton@math.udel.edu
Fioralba Cakoni, U of Delaware

The linear sampling method is an algorithm for solving the inverse scattering problem for acoustic and electromagnetic waves. The first version of the linear sampling method is more flexible, being able to treat the aforementioned cases as well as partially coated obstacles. However, its mathematical foundation is less well established. In this paper we provide arguments giving a mathematical justification of the first version of the linear sampling method. Fioralba is supported by NSF GIG DMS-9631287; David is supported by AFOSR.

DuPont
A Theoretical Formulation for Rapid, Unambiguous Polymer Characterization using Flow-Referenced Capillary Viscometers
Pam Cook (PI), cook@math.udel.edu
Emeka Nwankwo, DuPont
Gilberto Schleiniger, U of Delaware (PI), schleini@math.udel.edu
Bryan Wood, U of Delaware

The behavior of a polymer solution in a small tube has been studied and a paper has been submitted for publication. Pam and Gilberto have been supported by ATE grants from DuPont and Bryan is supported by DuPont and NSF GIG DMS-9631287.

Air Force
The direct and Inverse Scattering Problems for Partially Coated Obstacles
Peter Monk (PI), monk@math.udel.edu
Fioralba Cakoni, U of Delaware
David Colton, U of Delaware

The direct and inverse scattering problems for partially coated obstacles is considered. The method of integral equations of the first kind is used to solve a scattering problem for the Helmholtz equation where the scattered field satisfies mixed Dirichlet-impedance boundary conditions on the Lipschitz boundary of the scatterer $D$. Then the inverse scattering problem of determining $D$ from a knowledge of the far field pattern of the scattered field is solved by using the linear sampling method. Numerical examples are given showing the performance of the linear sampling method in this case. This work will appear in Inverse Problems; Peter is partially by, and Fioralba is fully supported by, NSF GIG DMS-9631287. Peter and David are supported by AFOSR.

AstroPower
Crystal Growth on a Substrate
Mikhail Khenner, U of Delaware
Richard Braun (PI), braun@math.udel.edu
Micheal Mauk, AstroPower

Crystal growth of a not-necessarily-thin film on a substrate with a mask is studied. The fully nonlinear surface geometry is taken into account with an isotropic geometric growth model including surface diffusion and condensation from the vapor. The results have been submitted for publication. This is a follow-on project from the MPI 1999 meeting held at UD. Rich is partially supported by, and Mikhail is fully supported by, NSF GIG DMS-9631287. The paper from this isotropic model is "An Isotropic Model for Crystal Growth from Vapor on a Patterned Substrate," M. Khenner, R.J. Braun and M.G. Mauk, J. Crystal Growth, 235 (2002) 425-438.

Dow Corning
Bounded film evolution with variable surface properties
Cynthia DeBisschop, now at Old Dominion University
Richard Braun (PI), braun@math.udel.edu
Steven Snow, Dow Corning

In this project, theory is being developed for a thin film on a plate with nonlinear surface properties. The results are of interest to Dow Corning and will allow us to tackle a wider range of problems of interest to them. Dow Corning is partially supporting Rich; Rich is partially supported by, and Cyndi was fully supported by, NSF GIG DMS-9631287.

Air Force
The Linear Sampling Method for Anisotropic Media
David Colton (PI), colton@math.udel.edu
Fioralba Cakoni, U of Delaware
Houssem Haddar, U of Delaware

We consider the inverse scattering problem of determining the support of an anisotropic inhomogeneous medium from a knowledge of the incident and scattered time harmonic acoustic wave at fixed frequency. To this end we extend the linear sampling method from the isotropic case to the case of anisotropic media. In the case when the coefficients are real we also show that the set of transmission eigenvalues forms a discrete set. This work will appear in Journal of Computational and Applied Mathematics; Fioralba is supported by NSF GIG DMS-9631287; David is supported by AFOSR.

Air Force
The Linear Sampling Method for Anisotropic Media: Part II
Fioralba Cakoni (PI), cakoni@math.udel.edu
Houssem Haddar, U of Delaware

We reconsider the linear sampling method for solving the inverse scattering problem of determining the support of an anisotropic inhomogeneous medium from a knowledge of the incident and scattered time harmonic acoustic wave at fixed frequency. We extend the results of a previous paper concerning with the same problem to the case where the norm of the real part of the matrix that describes the physical properties of the medium is less than one. This work is in Preprint No. 2001-026, Mathematical Sciences Research Institute, University of California at Berkeley; Fioralba is supported by NSF GIG DMS-9631287.

Dow Corning
Vertical bounded film evolution with variable surface properties
Homayoun Heidari, Sharif University of Technology, Iran (visiting RPI and UD)
Richard Braun (PI), braun@math.udel.edu
Amir Hirsa, Rensselaer Polytechnic Institute
Steven Snow, Dow Corning
Shailesh Naire, University of Nottingham, UK

In this project, theory is being developed for a thin film on a vertical plate with nonlinear surface properties. The results are of interest to Dow Corning and will allow us to make very detailed comparison with experiments that have been developed at RPI. Dow Corning is supporting Rich and Homayoun; Rich is partially supported by NSF GIG DMS-9631287.

SmithKline Beecham
Summer 2000 Internship
Ellen Phifer, U of Delaware
Larry Greller, SmithKline Beecham
Frank Tobin, SmithKline Beecham

Ellen Phifer spent the summer analyzing and improving upon a variable tension spline curve-fitting package. The resulting code was incorporated into MATLAB and will be used by mathematical biologists at SmithKline Beecham in their analysis of sparse data sets. Her studies were directed by Larry Greller and Frank Tobin.

Merck
Summer 2000 Internship
Chrissy Getman, U of Delaware

Mathematical Problems in Industry Workshop 2000
Richard Braun, braun@math.udel.edu
Pam Cook
David Edwards, edwards@math.udel.edu
Peter Monk
Petr Plechac
Gilberto Schleiniger
Don Schwendeman, Rensselaer Polytechnic Institute

The Department of Mathematical Sciences hosted the 16th annual Mathematical Problems in Industry workshop June 5-9, 2000. Thank you to NIST for valuable support once again!

Mathematical Problems in Industry Workshop 1999
Richard Braun, braun@math.udel.edu
Pam Cook
David Edwards
Peter Monk
David Olagunju
Gilberto Schleiniger
Don Schwendeman, Rensselaer Polytechnic Institute

The Department of Mathematical Sciences hosted the 15th annual Mathematical Problems in Industry workshop in early June 1999. The MPI workshop has been held at Rensselaer Polytechnic Institute for the last 13 years (with one exception, when it was held at the University of New Mexico). We were very excited about this week-long international workshop where industrial problems are presented and studied. The workshop was partially supported by a grant from the Mathematical and Computational Sciences Division at the National Institute of Standards and Technology; thank you NIST!

Brooks Air Force Base
Inverse problem for detection of underground objects
Joe Coyle,
Peter Monk, monk@math.udel.edu
David Colton (PI), colton@math.udel.edu
Richard Albanese, Brooks AFB

Joe Coyle spent the summer of 1997 at Brooks AFB in San Antonio, TX, under the supervision of Richard Albanese studying inverse problems related to the detection of underground objects. This work has formed a substantial part of his PhD thesis with Peter Monk.

Dow Corning
Gravitationally-driven drainage of a thick film with a tangentially-immobile surface
Richard Braun (PI), braun@math.udel.edu
Steven Snow, Dow Corning
Udo Pernisz, Dow Corning

In this project, theory was necessary for an experiment that Steven Snow and Udo Pernisz developed at Dow Corning. Their experiment can produce detailed information about the dhape of a film suspended from a wire frame and draining vertically into a bath. In a limiting regime of the experiments, the surface of the film can be made tangentially immobile. We have have developed a theory for this case where we use singular pertubation and computational methods to solve the problem.

From this work we have written a Dow Corning internal report (I0000-1998-45018 by Braun, Snow and Pernisz) and a paper has appeared (J. Colloid Interface Sci. 219 (1999) 225-240). This material is based upon work supported in part by the National Science Foundation under Grant No. 9631287.


Dow Corning
Limiting cases of gravitationally-driven drainage of thick film
Shailesh Naire
Richard Braun (PI), braun@math.udel.edu
Steven Snow, Dow Corning

In this project, theory was necessary for an experiment that Steven Snow and Udo Pernisz developed at Dow Corning. Their experiment can produce detailed information about the shape of a film suspended from a wire frame and draining vertically into a bath. Shailesh Naire has extended the work on the case of a tangentially-immobile film (see below) to include more realistic physical effects. Finite surface viscosity, the Marangoni effect, and surfactant transport have been added. A "flat film" limit has been studied. Shailesh has solutions from analytical and computional approaches that bound the fastest and slowest draining limits of the experiments.

This work has appeared electronically in the SIAM Journal on Applied Mathematics (61 (2000) 889-913), and has resulted in the Dow Corning internal report (1999-I0000-41799). This material is based upon work supported in part by the National Science Foundation under Grant No. 9631287.


Dow Corning
Insoluble surfactant model for gravitationally-driven drainage of a thick film
Shailesh Naire
Richard Braun (PI), braun@math.udel.edu
Steven Snow, Dow Corning

In this project, theory was necessary for an experiment that Steven Snow and Udo Pernisz developed at Dow Corning. Their experiment can produce detailed information about the shape of a film suspended from a wire frame and draining vertically into a bath. Shailesh Naire has extended the work still further. Finite surface viscosity, the Marangoni effect, and surfactant transport have been added, and the case where the film is patched onto the static meniscus has been studied. He also has found interesting dynamics in the evolution of the film shape and other dependent variables. These 1+1-d computations have appeared in the Journal of Colloid and Interface Science (230 (2000) 91-106). This material is based upon work supported in part by the National Science Foundation under Grant No. 9631287.

Dow Corning
Gravitationally-driven drainage of a thick film in 3D
Shailesh Naire, now going to the University of Nottingham, UK
Richard Braun (PI), braun@math.udel.edu
Steven Snow, Dow Corning

Dow Corning
Gravitationally-driven vertical film drainage with variable surface properties
Shailesh Naire, now at Divsion of Theoretical Mechanics, University of Nottingham, UK
Richard Braun (PI), braun@math.udel.edu
Steven Snow, Dow Corning

Shailesh added nonlinear surface properties to the one-dimensional film problem and the results have appeared in print (Phys. Fluids 13, (2001) 2492-2502). Dow Corning supported Shailesh and Rich; this material is based upon work supported in part by the National Science Foundation under Grant No. 9631287.

Shailesh completed a set of 2+1 dimensional computations and the results have been submitted to the Journal of Fluid Mechanics. Dow Corning supported Shailesh and Rich; this material is based upon work supported in part by the National Science Foundation under Grant No. 9631287.

National Institute of Standards and Technology
Effect of initial conditions in phase-field modeling of dendritic growth
Jie Zhang, now at Northwestern University
Richard Braun, , braun@math.udel.edu
Bruce Murray, SUNY Binghamton
Jeff McFadden, NIST

In this internship, Jie spent two months of the summer of 1996 at the NIST Gaithersburg, MD, site. There he worked with Bruce Murray (then of NIST) and Jeff McFadden in the Applied and Computational Mathematics Division of the Information Technology Laboratory. Jie also attended a short course on diffuse-interface modeling of phase change.

Jie studied the effect of different initial conditions on the subsequent evolution Governed by a phase field model of solidification. Jie computed the solidification of an undercooled melt in a thermally-insulated box with initial conditions for the thermal field that could be discontinuous, have only a continuous temperature field, or have a continuous first derivative as well. He found that the smoother the initial condition for the temperature field was, the less likely it would be that unphysical spreading of the interfacial region would occur. This is practically useful in computation of dendritic microstructures and the results will soon be available in postscript form.

Jie did this project for MS thesis in the Math Sciences Department. He is now attending the Northwestern Department of Engineering Sciences and Applied Mathematics and is studying for his PhD there.


Thomson CSF, France
Inverse scattering of electromagnetic waves from obstacles
Cristoph Labreuch, Thomson CSF
Peter Monk, monk@math.udel.edu
David Colton (PI), colton@math.udel.edu

Drs Colton and Monk were visited for a year by Christoph Labreuch, an employee of Thomson CSF, to study the identification of objects using inverse scattering of electromagnetic waves. This work formed the bulk of Christoph's PhD thesis.

Equipment for the Lab
Peter Monk, monk@math.udel.edu
Pam Cook, cook@math.udel.edu
Richard Braun, braun@math.udel.edu

An SGI Octane with an R10000 cpu, an SGI Indigo2 with an R10000 cpu, and a Pentium III machine are in an office suite in Ewing Hall. Shailesh wasvworking away and Peter and Joe collaborating.


  • UD Department of Mathematical Sciences  •   501 Ewing Hall   •   Newark, DE 19716  •   USA
    Phone: 302-831-2653  •  Fax: 302-831-4511  •   E-mail: www@math.udel.edu