14 research outputs found
ΠΠ°ΡΠΈΡΠ΅Π½ΡΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΊΠΎΠΎΡΠ΄ΠΈΠ½Π°ΡΡ ΠΡΠ°ΡΡΠΎΠ½Π° β Π ΠΈΠΌΠ°Π½Π°
The article deals with the problem of finding barycentric coordinates for arbitrary, simply connected, closed, discrete regions that are defined in and . Barycentric coordinates are given by a set of scalar parameters that unambiguously define a point of the affine space inside a simply connected, closed, discrete region through a specified point basis, which is given by the vertices of the region. BarycentriΡ coordinates being defined for the simply connected, closed, discrete region are harmonic and satisfy the properties of affine invariance, positive definiteness and equality to unit. The solution is based on the Riemann theorem on the uniqueness of conformal mapping and the Poisson integral formula for the ball. The paper shows the examples of approximation of the potential inside arbitrary, simply connected, closed, discrete regions using the proposed method, compared with the approximation using the finite element method.Π ΡΡΠ°ΡΡΠ΅ Π²ΡΠΏΠΎΠ»Π½Π΅Π½ΠΎ ΡΠ΅ΡΠ΅Π½ΠΈΠ΅ Π·Π°Π΄Π°ΡΠΈ Π½Π°Ρ
ΠΎΠΆΠ΄Π΅Π½ΠΈΡ Π±Π°ΡΠΈΡΠ΅Π½ΡΡΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΊΠΎΠΎΡΠ΄ΠΈΠ½Π°Ρ Π΄Π»Ρ ΠΏΡΠΎΠΈΠ·Π²ΠΎΠ»ΡΠ½ΡΡ
ΠΎΠ΄Π½ΠΎΡΠ²ΡΠ·Π½ΡΡ
Π·Π°ΠΌΠΊΠ½ΡΡΡΡ
Π΄ΠΈΡΠΊΡΠ΅ΡΠ½ΡΡ
ΠΎΠ±Π»Π°ΡΡΠ΅ΠΉ, Π·Π°Π΄Π°Π½Π½ΡΡ
Π² ΠΈ . ΠΠ°ΡΠΈΡΠ΅Π½ΡΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΊΠΎΠΎΡΠ΄ΠΈΠ½Π°ΡΡ Π·Π°Π΄Π°ΡΡΡΡ Π½Π°Π±ΠΎΡΠΎΠΌ ΡΠΊΠ°Π»ΡΡΠ½ΡΡ
ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠΎΠ², ΠΎΠ΄Π½ΠΎΠ·Π½Π°ΡΠ½ΠΎ ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΡΡΠΈΡ
ΡΠΎΡΠΊΡ Π°ΡΡΠΈΠ½Π½ΠΎΠ³ΠΎ ΠΏΡΠΎΡΡΡΠ°Π½ΡΡΠ²Π° Π²Π½ΡΡΡΠΈ ΠΎΠ΄Π½ΠΎΡΠ²ΡΠ·Π½ΠΎΠΉ Π·Π°ΠΌΠΊΠ½ΡΡΠΎΠΉ Π΄ΠΈΡΠΊΡΠ΅ΡΠ½ΠΎΠΉ ΠΎΠ±Π»Π°ΡΡΠΈ ΡΠ΅ΡΠ΅Π· Π·Π°Π΄Π°Π½Π½ΡΠΉ ΡΠΎΡΠ΅ΡΠ½ΡΠΉ Π±Π°Π·ΠΈΡ. Π’ΠΎΡΠ΅ΡΠ½ΡΠΉ Π±Π°Π·ΠΈΡ Π·Π°Π΄Π°Π΅ΡΡΡ Π²Π΅ΡΡΠΈΠ½Π°ΠΌΠΈ ΠΎΠ΄Π½ΠΎΡΠ²ΡΠ·Π½ΠΎΠΉ Π·Π°ΠΌΠΊΠ½ΡΡΠΎΠΉ Π΄ΠΈΡΠΊΡΠ΅ΡΠ½ΠΎΠΉ ΠΎΠ±Π»Π°ΡΡΠΈ. ΠΠΏΡΠ΅Π΄Π΅Π»ΡΠ΅ΠΌΡΠ΅ Π±Π°ΡΠΈΡΠ΅Π½ΡΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΊΠΎΠΎΡΠ΄ΠΈΠ½Π°ΡΡ Π΄Π»Ρ ΠΎΠ΄Π½ΠΎΡΠ²ΡΠ·Π½ΠΎΠΉ Π·Π°ΠΌΠΊΠ½ΡΡΠΎΠΉ Π΄ΠΈΡΠΊΡΠ΅ΡΠ½ΠΎΠΉ ΠΎΠ±Π»Π°ΡΡΠΈ ΡΠ²Π»ΡΡΡΡΡ Π³Π°ΡΠΌΠΎΠ½ΠΈΡΠ΅ΡΠΊΠΈΠΌΠΈ ΠΈ ΡΠ΄ΠΎΠ²Π»Π΅ΡΠ²ΠΎΡΡΡΡ ΡΠ²ΠΎΠΉΡΡΠ²Π°ΠΌ Π°ΡΡΠΈΠ½Π½ΠΎΠΉ ΠΈΠ½Π²Π°ΡΠΈΠ°Π½ΡΠ½ΠΎΡΡΠΈ, ΠΏΠΎΠ»ΠΎΠΆΠΈΡΠ΅Π»ΡΠ½ΠΎΠΉ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½Π½ΠΎΡΡΠΈ ΠΈ ΡΠ°Π²Π΅Π½ΡΡΠ²Π΅ Π΅Π΄ΠΈΠ½ΠΈΡΠ΅. Π Π΅ΡΠ΅Π½ΠΈΠ΅ ΠΎΡΠ½ΠΎΠ²Π°Π½ΠΎ Π½Π° ΡΠ΅ΠΎΡΠ΅ΠΌΠ΅ Π ΠΈΠΌΠ°Π½Π° ΠΎ Π΅Π΄ΠΈΠ½ΡΡΠ²Π΅Π½Π½ΠΎΡΡΠΈ ΠΊΠΎΠ½ΡΠΎΡΠΌΠ½ΠΎΠ³ΠΎ ΠΎΡΠΎΠ±ΡΠ°ΠΆΠ΅Π½ΠΈΡ ΠΈ ΠΈΠ½ΡΠ΅Π³ΡΠ°Π»ΡΠ½ΠΎΠΉ ΡΠΎΡΠΌΡΠ»Π΅ ΠΡΠ°ΡΡΠΎΠ½Π° Π΄Π»Ρ ΡΠ°ΡΠ°. ΠΡΠΈΠ²Π΅Π΄Π΅Π½Ρ ΠΏΡΠΈΠΌΠ΅ΡΡ Π°ΠΏΠΏΡΠΎΠΊΡΠΈΠΌΠ°ΡΠΈΠΈ ΠΏΠΎΡΠ΅Π½ΡΠΈΠ°Π»Π° Π²Π½ΡΡΡΠΈ ΠΏΡΠΎΠΈΠ·Π²ΠΎΠ»ΡΠ½ΡΡ
ΠΎΠ΄Π½ΠΎΡΠ²ΡΠ·Π½ΡΡ
Π·Π°ΠΌΠΊΠ½ΡΡΡΡ
Π΄ΠΈΡΠΊΡΠ΅ΡΠ½ΡΡ
ΠΎΠ±Π»Π°ΡΡΠ΅ΠΉ ΠΏΠΎ ΠΏΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½Π½ΠΎΠΌΡ ΠΌΠ΅ΡΠΎΠ΄Ρ Π² ΡΡΠ°Π²Π½Π΅Π½ΠΈΠΈ Ρ Π°ΠΏΠΏΡΠΎΠΊΡΠΈΠΌΠ°ΡΠΈΠ΅ΠΉ ΠΌΠ΅ΡΠΎΠ΄ΠΎΠΌ ΠΊΠΎΠ½Π΅ΡΠ½ΡΡ
ΡΠ»Π΅ΠΌΠ΅Π½ΡΠΎΠ²
Addressing Integration Error for Polygonal Finite Elements Through Polynomial Projections: A Patch Test Connection
Polygonal finite elements generally do not pass the patch test as a result of
quadrature error in the evaluation of weak form integrals. In this work, we
examine the consequences of lack of polynomial consistency and show that it can
lead to a deterioration of convergence of the finite element solutions. We
propose a general remedy, inspired by techniques in the recent literature of
mimetic finite differences, for restoring consistency and thereby ensuring the
satisfaction of the patch test and recovering optimal rates of convergence. The
proposed approach, based on polynomial projections of the basis functions,
allows for the use of moderate number of integration points and brings the
computational cost of polygonal finite elements closer to that of the commonly
used linear triangles and bilinear quadrilaterals. Numerical studies of a
two-dimensional scalar diffusion problem accompany the theoretical
considerations