DID YOU KNOW? DTIC has over 3.5 million final reports on DoD funded research, development, test, and evaluation activities available to our registered users. Click
HERE to register or log in.
Accession Number:
ADA151896
Title:
Investigation of the Numerical Method of Moments for Digital Computer Determination of Differential Equations.
Descriptive Note:
Master's thesis,
Corporate Author:
AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING
Report Date:
1984-12-01
Pagination or Media Count:
91.0
Abstract:
The purpose of this thesis was to determine the feasibility of using the method of weighted residuals to obtain approximations to the discrete Greens function, or analogs to it. The weighted residual methods of Galerkin and collocation, as well as the finite difference method were programmed of a Kaypro II micro-computer in Microsoft Basic. These programs were used to generate approximations to the one- and two-dimensional Poissons equation, The two-dimensional case was restricted to the geometry of a unit square. Various inhomogeneity terms were used to obtain approximate solutions to the discrete Greens functions or their analogs. The results were compared with the analytical values at various interior nodal points on the mesh. The average percent error for the approximations were reported for each case as the number of interior nodal points was increased. The areas of consideration were the rate of convergence to the analytical solution, the amount of time it took to run each program, and the accuracy of the approximate solutions. The results of this study indicate that the Greens functions or analogs obtained are valid approximations to the discrete Greens functions or analogs obtained are valid approximations to the discrete Greens functions. The method of weighted residuals proved to be very sensitive to the choice of basis functions, resulting in ill-conditioned matrices in some instances. Author
Distribution Statement:
APPROVED FOR PUBLIC RELEASE
