Plenary
Lecture
Analytical and Boundary Elements based Integral
Representation for Numerical Solution of 3-D Potential
Problems in Heterogeneous Media Containing Singularities

Professor Ioan David
POLITEHNICA University Timisoara
Romania
E-mail: Ioan.David@gmx.net
Abstract: Mathematical formulation of processes in
different areas of physics, e. g. fluid flows and
transport phenomena through porous media, electrostatics
and electrodynamics, heat conduction etc. lead to
boundary value problems for partially differential
equation elliptical type. In many engineering
applications, the processes mentioned above, have
behaviours that mathematically represent singularities
(point sources/sinks or line sources/sinks etc. in 2-D
or 3-D domain). Generally the numerical solutions with
classical numerical methods like FVM or FVM lead to
difficulties.
In the paper a solution that eliminates these
difficulties and shortcomings are present a method based
on integral representation of the solution, combining
the Analytical Elements and Boundary Elements which will
be called AE-BEM. The presentation will be focused
especially on the flow problems in porous media where
the singularities are wells or drains shaped as thin
objects of finite length etc.
The 3-D flow domain is constituted of several arbitrary
distributed sub-domains with different conductivity’s
(e.g. hydraulic conductivity) called
Non-Singularity-Objects (NSO) and several point-
source/sink line-source/sink as sub-domains called
Singularity-Objects (SO) which can be located
arbitrarily regarding the NSO. On the boundary of the
NSO transition conditions between the internal and
external flow should be satisfied while on the boundary
of the SO only boundary conditions for the external
process are required. The singular integral
representation of the solution of boundary value
problems for each object will be used as theoretical
base of the AE-BEM. In the paper we present several
examples for 3-D flow simulation obtained on the basis
of the proposed AE-BEM and its software implementation.
|