caa a22 4500 445387300 CHVBK 20180317143035.0 cr unu---uuuuu 170323e20110501xx s 000 0 eng 10.1007/s10714-010-1096-z doi (NATIONALLICENCE)springer-10.1007/s10714-010-1096-z Thornburg Jonathan Department of Astronomy, Indiana University, Bloomington, IN, USA aut Adaptive mesh refinement for characteristic grids [Elektronische Daten] [Jonathan Thornburg] I consider techniques for Berger-Oliger adaptive mesh refinement (AMR) when numerically solving partial differential equations with wave-like solutions, using characteristic (double-null) grids. Such AMR algorithms are naturally recursive, and the best-known past Berger-Oliger characteristic AMR algorithm, that of Pretorius and Lehner (J Comp Phys 198:10, 2004), recurses on individual "diamond” characteristic grid cells. This leads to the use of fine-grained memory management, with individual grid cells kept in two-dimensional linked lists at each refinement level. This complicates the implementation and adds overhead in both space and time. Here I describe a Berger-Oliger characteristic AMR algorithm which instead recurses on null slices. This algorithm is very similar to the usual Cauchy Berger-Oliger algorithm, and uses relatively coarse-grained memory management, allowing entire null slices to be stored in contiguous arrays in memory. The algorithm is very efficient in both space and time. I describe discretizations yielding both second and fourth order global accuracy. My code implementing the algorithm described here is included in the electronic supplementary materials accompanying this paper, and is freely available to other researchers under the terms of the GNU general public license. Springer Science+Business Media, LLC, 2010 Adaptive mesh refinement nationallicence Finite differencing nationallicence Characteristic coordinates nationallicence Characteristic grids nationallicence Berger-Oliger algorithm nationallicence General Relativity and Gravitation Springer US; http://www.springer-ny.com 43/5(2011-05-01), 1211-1251 0001-7701 43:5<1211 2011 43 10714 https://doi.org/10.1007/s10714-010-1096-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10714-010-1096-z text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Thornburg Jonathan Department of Astronomy, Indiana University, Bloomington, IN, USA aut NATIONALLICENCE 773 0- General Relativity and Gravitation Springer US; http://www.springer-ny.com 43/5(2011-05-01), 1211-1251 0001-7701 43:5<1211 2011 43 10714 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer