Háskóli ÍslandsUniversity of IcelandHelgadottir, AsdisNg, Yen TingMin, ChohongGibou, Frédéric2019-05-072019-05-072015-10Ásdís Helgadóttir, Yen Ting Ng, Chohong Min, Frédéric Gibou, Imposing mixed Dirichlet–Neumann–Robin boundary conditions in a level-set framework, Computers & Fluids, Volume 121, 2015, Pages 68-80, ISSN 0045-7930, https://doi.org/10.1016/j.compfluid.2015.08.0070045-7930https://hdl.handle.net/20.500.11815/1153Pre-print (óritrýnt handrit)We consider the Poisson equation with mixed Dirichlet, Neumann and Robin boundary conditions on irregular domains. We describe a straightforward and efficient approach for imposing the mixed boundary conditions using a hybrid finite-volume/finite-difference approach, leveraging on the work of Gibou et al. (2002) [14], Ng et al. (2009) [30] and Papac et al. (2010) [33]. We utilize three different level set functions to represent the irregular boundary at which each of the three different boundary conditions must be imposed; as a consequence, this approach can be applied to moving boundaries. The method is straightforward to implement, produces a symmetric positive definite linear system and second-order accurate solutions in the L-infinity-norm in two and three spatial dimensions. Numerical examples illustrate the second-order accuracy and the robustness of the method. (C) 2015 Elsevier Ltd. All rights reserved.68-80eninfo:eu-repo/semantics/openAccessFinite differenceLevel setMixed boundary conditionsTöluleg greiningLíkindafræðiinfo:eu-repo/semantics/articleComputers & Fluids10.1016/j.compfluid.2015.08.007