diff --git a/joss/paper.md b/joss/paper.md index 47f1ca348..05c5c8c3c 100644 --- a/joss/paper.md +++ b/joss/paper.md @@ -1,162 +1,161 @@ --- title: 'Akantu: an HPC finite-element library for contact and fracture simulations' tags: - C++ - cohesive element - contact - fracture - python authors: - name: Nicolas Richart orcid: 0000-0002-1463-4405 affiliation: 1 - name: Guillaume Anciaux orcid: 0000-0002-9624-5621 affiliation: 1 - name: Emil Gallyamov affiliation: 1 - name: Lucas Frérot orcid: 0000-0002-4138-1052 affiliation: "1, 2" - name: David Kammer orcid: 0000-0003-3782-9368 affiliation: "1, 3" - name: Mohit Pundir affiliation: "1, 3" - name: Marco Vocialta affiliation: 1 - name: Aurelia Cuba Ramos affiliation: 1 - name: Mauro Corrado affiliation: "1, 4" - name: Fabian Barras orcid: 0000-0003-1109-0200 affiliation: "1, 5" - name: Jean-François Molinari orcid: 0000-0002-1728-1844 affiliation: 1 affiliations: - name: Civil Engineering Institute, École Polytechnique Fédérale de Lausanne, Switzerland index: 1 - name: Department of Microsystems Engineering, Univeristy of Freiburg, Germany index: 2 - name: Institute for Building Materials, ETH Zurich, Switzerland index: 3 - name: Department of Structural, Geotechnical and Building Engineering, Politecnico di Torino, Italy index: 4 - name: The Njord Centre Department of Physics, Department of Geosciences, University of Oslo, Norway index: 5 date: February 2023 bibliography: paper.bib --- # Summary Complex, nonlinear and transient phenomena are at the heart of modern research in mechanics of materials. For example, the buildup and release of elastic energy at geological fault is what causes earthquakes, and the intricate details of the slip zone, the propagation of slip fronts and waves radiated through the various geological media are still active areas of research [@kammer_propagation_2012;@kammer_existence_2014]. Similarly, understanding fracture in heterogeneous materials such as concrete, masonry or ceramics necessitates the modeling of interaction of crack fronts with complex materials [@taheri_mousavi_dynamic_2015;@yilmaz_damage_2017;@cuba_ramos_hpc_2018], the representation of residual shear stresses in the contact of newly-formed crack surfaces [@zhang_micro-mechanical_2017;@pundir_coupling_2021], and the accurate characterization of transient dynamics [@vocialta_numerical_2018;@corrado_effects_2016] and material structure evolution [@cuba_ramos_hpc_2018;@gallyamov_multi-scale_2020]. The finite-element method is now ubiquitous in virtually all areas of solid mechanics. With meticulous care on code architecture and performance, we show with our finite-element library Akantu that it can handle the requirements mentioned above for state-of-the-art research in mechanics of materials. Akantu is designed from the ground up for high-performance, highly distributed computations, while retaining the necessary flexibility to handle: - crack propagation with cohesive elements - non-local damage models - plastic and visco-plastic constitutive laws - large deformations - contact constraints (including friction) - structural elements (beams and shells) - one-dimensional elements embedded in a three-dimensional mesh (e.g. reinforcements in concrete) - interaction between contact and cohesive elements (residual crack shear strength) # Statement of need Understanding the interplay between material constitutive behavior and interface processes such as crack propagation, contact and friction is fundamental to the study of, among others, earthquakes, concrete structures, ceramics, and poly-crystalline failure. Thanks to its versatility, the finite-element method (FEM) has become a staple in these areas. However, codes that can handle cutting edge simulations with interaction of material behavior and interface processes in a high-performance computing (HPC) setting are rare, particularity in the open-source space. Driving these state-of-the-art research simulations to the exascale era is the primary *raison d'être* of Akantu. At its heart, Akantu leverages a SOA (structure of array) architecture in order -to take advantage from object-oriented high-level abstraction, and maintain +to take advantage of an object-oriented high-level abstraction, and maintain performance in the critical areas of the code. In addition Akantu, benefits from distributed memory parallelization, and on the contrary to many finite-element -codes, Akantu as a element centric parallelization that makes it easier to +codes, Akantu has a element-centric parallelization that makes it easier to implement algorithms like the dynamic insertion of extrinsic cohesive elements. # Scaling analysis - ![Time to solution with and without cohesive insertion.\label{fig:tts}](results/TTS.svg) High performance and scalability is a necessity for the resolution of fracture and contact simulations. To illustrate the possibilities offered by Akantu, a 3D simulation is presented where a cube composed of 4'392'180 tetrahedra and 734'594 nodes is being compressed and sheared. -This simulation has for only purpose to demonstrate how Akantu behaves during a simulation -where massive fragmentation takes place: ~460'000 cohesive elements were inserted during the run. -This simulation was ran on 1 up to 720 cores, on a cluster composed of Intel Xeon nodes with 2 sockets of 36 -cores, 512Gb of RAM and dual 25Gb Ethernet links. The average time to solution (TTS) -computed over six different runs is computed for each core number on the $x$-axis in Figure \autoref{fig:tts}. +This simulation only serves to demonstrate how Akantu behaves in a situation +where massive fragmentation takes place: about 460'000 cohesive elements are inserted during the run. +This simulation was run on 1 up to 720 cores, on a cluster composed of Intel Xeon nodes with 2 sockets of 36 +cores, 512Gb of RAM and dual 25Gb Ethernet links. The time to solution (TTS) +averaged over six different runs is computed for each core count on the $x$-axis in Figure \autoref{fig:tts}. The overhead due to cohesive element insertion is also highlighted by providing the timings when cohesive element insertions are precluded. # Publications The following publications have been made possible with Akantu: - @kammer_propagation_2012 - @kammer_existence_2014 - @wolff_non-local_2014 - @richart_implementation_2015 - @taheri_mousavi_dynamic_2015 - @cuba_ramos_new_2015 - @radiguet_role_2015 - @vocialta_influence_2015 - @corrado_effects_2016 - @kammer_length_2016 - @svetlizky_properties_2016 - @vocialta_3d_2016 - @yilmaz_mesoscale_2017 - @yilmaz_damage_2017 - @zhang_micro-mechanical_2017 - @cuba_ramos_hpc_2018 - @vocialta_numerical_2018 - @yilmaz_influence_2018 - @zhang_numerical_2018 - @zhang_numerical_2019 - @frerot_fourier_2019 - @gallyamov_multi-scale_2020 - @milanese_mechanistic_2020 - @albertini_three-dimensional_2021 - @brun_hybrid_2021 - @rezakhani_meso-scale_2021 - @pundir_coupling_2021 # Acknowledgement The development of Akantu would not have been possible without the support of the European Research Council ERCstg UFO-240332, the Swiss Federal Office of Energy contract No. SI/500852-01, Swiss National Science Foundation grant number CRSII5_17108 # References