A Finite Point Method Based on Directional Derivatives for Diffusion Equation

This paper presents a finite point method based on directional derivatives for diffusion equation on 2D scattered points. To discretize the diffusion operator at a given point, a six-point stencil is derived by employing explicit numerical formulae of directional derivatives, namely, for the point under consideration, only five neighbor points are involved, the number of which is the smallest for discretizing diffusion operator with first-order accuracy. A method for selecting neighbor point set is proposed, which satisfies the solvability condition of numerical derivatives. Some numerical examples are performed to show the good performance of the proposed method.




References:
[1] L. J. Shen, G. X. Lv and Z. J. Shen, "A Finite Point Method Based on
Directional Differences", SIAM J. Numer. Anal., vol. 47(3), pp. 2224-
2242, 2009.
[2] G. X. Lv, L. J. Shen and Z. J. Shen, "Study on Finite Point Method",
Chinese J. comput. phys., vol. 25(5), pp. 505-524, 2008.
[3] E. O˜nate, S. Idelsohn, O. C. Zienkiewicz, and R. L. Taylor, "A finite point
method in computing mechanics application to convective transport and
fluid flow", Internat. J. Numer. Methods Engrg., vol. 39, pp. 3839-3866,
1996.
[4] B. Boroomand, A. A. Tabatabaei, and E. O˜nate, "Simple modifications
for stabilization of the finite point method", Intern. J. Numer. Methods
Engrg., vol. 63, pp. 351-379, 2005.
[5] Z. J. Shen, L. J. Shen, G. X. Lv,W. Chen, and G. W. Yuan, "A Lagrangian
finite point method for two-dimensional fluid dynamic problems", Chinese
J. comput. phys., vol. 22(5), pp. 377-385, 2005.
[6] D. Sridar and N. Balakrishnan, "An upwind finite difference scheme for
meshless solvers", J. Comput. Phys., vol. 189, pp. 1-29, 2003.
[7] P. S. Jensen, "Finite difference techniques for variable grids", Comp.
Structures, vol. 2, pp. 17-29, 1972.
[8] K. C. Chung, "A generalized finite difference method for heat transfer
problems of irregular geometries", Numer. Heat Transfer, Part A: Applications,
vol. 4, pp. 345-357, 1981.
[9] G. B. Wright and B. Fornberg, "Scattered node compact finite differencetype
formulas generated from radial basis functions", J. Comput. Phys.,
vol. 212, pp. 99-123, 2006.
[10] J. M. Wu, Z. H. Dai, Z. M. Gao and G. W. Yuan, "The linearity preserving
nine-point schemes for diffusion equation on distorted quadrilateral
meshes", J. Comput. Phys., vol. 229, pp. 3382-3401, 2010.