LAUSR

This work presents a vision of future water resources hydrodynamics codes that can fully utilize the strengths of modern high-performance computing (HPC). The advances to computing power, formerly driven by the improvement of central processing unit processors, now focus on parallel computing and, in particular, the use of graphics processing units (GPUs). However, this shift to a parallel framework requires refactoring the code to make efficient use of the data as well as changing even the nature of the algorithm that solves the system of equations. These concepts along with other features such as the precision for the computations, dry regions management, and input/ output data are analyzed in this paper. A 2D multi-GPU flood code applied to a large-scale test case is used to corroborate our statements and ascertain the new challenges for the next-generation parallel water resources codes. doi: 10.2166/hydro.2020.163 ://iwaponline.com/jh/article-pdf/22/5/1217/761454/jh0221217.pdf M. Morales-Hernández (corresponding author) K. J. Evans Computational Sciences and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA E-mail: [email protected] M. Morales-Hernández S. Gangrade S.-C. Kao K. J. Evans Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA M. B. Sharif S. K. Ghafoor Department of Computer Science, Tennessee Technological University, Cookeville, TN 38505, USA S. Gangrade S.-C. Kao Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA T. T. Dullo A. Kalyanapu Department of Civil and Environmental Engineering, Tennessee Technological University, Cookeville, TN 38505, USA E. Madadi-Kandjani B. R. Hodges National Center for Infrastructure Modeling and Management, University of Texas at Austin, Austin, TX 78758, USA