Adaptation and Performance of the Cartesian Coordinates Fast Multipole Method for Nanomagnetic Simulations - Physics > Computational PhysicsReport as inadecuate




Adaptation and Performance of the Cartesian Coordinates Fast Multipole Method for Nanomagnetic Simulations - Physics > Computational Physics - Download this document for free, or read online. Document in PDF available to download.

Abstract: An implementation of the fast multiple method FMM is performed for magneticsystems with long-ranged dipolar interactions. Expansion in spherical harmonicsof the original FMM is replaced by expansion of polynomials in Cartesiancoordinates, which is considerably simpler. Under open boundary conditions, anexpression for multipole moments of point dipoles in a cell is derived. Thesemake the program appropriate for nanomagnetic simulations, including magneticnanoparticles and ferrofluids. The performance is optimized in terms of cellsize and parameter set expansion order and opening angle and the trade offbetween computing time and accuracy is quantitatively studied. A rule of thumbis proposed to decide the appropriate average number of dipoles in the smallestcells, and an optimal choice of parameter set is suggested. Finally, thesuperiority of Cartesian coordinate FMM is demonstrated by comparison tospherical harmonics FMM and FFT.



Author: Wen Zhang, Stephan Haas

Source: https://arxiv.org/







Related documents