I propose to numerically address the question of finite time singularity development in the three-dimensional incompressible Euler equations with smooth initial data. These equations model the flow of incompressible ideal fluids. In particular, I will consider the axisymmetric with swirl case which allows for higher resolution than possible in fully three-dimensional experiments. Several different finite difference techniques will be implemented. I will investigate the performance of the different numerical schemes in order to assess the quality of each method. Also, I will study the effects different numerical boundary conditions have on vorticity amplification as well as the fully three-dimensional problem using particle methods. In conjunction with these experiments, I will perform numerical simulations of the Vlasov-Poisson equations in one dimension. These equations model a collisionless plasma of electrons in a uniform background of ions, and serve as a simpler analogue of the two-dimensional incompressible Euler equations. I will numerically study the behavior of weak solutions to the Vlasov-Poisson and Fokker-Planck-Poisson equations arising from non-smooth electron sheet initial data. An electron sheet describes a concentrated beam of electrons. The equations will be regularized by either smoothing the initial condition or by including collisions modeled by the Fokker-Planck-Poisson equations. I propose to use both a a finite difference method developed by Jack Schaeffer as well as particle methods to examine the solution of the Vlasov-Poisson equations obtained in the limit of vanishing regularization. And finally, this proposed research will prepare me to afterward conduct research related to the Boltzmann and Fokker-Planck equations with non-qmooth initial data which has potential medical appliations. These equations are used in the computation of dosage calculations in radiation therapy.

Agency
National Science Foundation (NSF)
Institute
Division of Mathematical Sciences (DMS)
Type
Standard Grant (Standard)
Application #
9709123
Program Officer
Lloyd E. Douglas
Project Start
Project End
Budget Start
1997-07-01
Budget End
1998-12-31
Support Year
Fiscal Year
1997
Total Cost
$18,000
Indirect Cost
Name
Ohio State University
Department
Type
DUNS #
City
Columbus
State
OH
Country
United States
Zip Code
43210