Hello, A yearly allocation for the LCRC cluster has been requested with the following updated information: Submitter/PI: Shashi Aithal Project Name: Nek5000 Division: MCS Project title: Scalable CFD Algorithms Associated funding: Applied Math Research Program, Nuclear Energy Advanced Modeling and Simulation Other Systems: ALCF Intrepid (BG/P), 128-core Linux cluster, Cosmea Science: Our mission is to develop and deploy scalable algorithms for simulation-based science applications that rely on numerical solution of partial differential equations. Our primary vehicle for algorithm development is the fluid/thermal simulation code, Nek5000, and its off-shoots, NekCEM (for computational electromagnetics) and NekLBM (for lattice Boltzmann methods). There are approximately 30 research groups worldwide currently using Nek5000. We use Nek5000---and the science applications brought to us through our user community---as vehicles for the development and test of new numerical algorithms that include stabilized high-order methods, scalable linear solvers, advanced timestepping methods, and so forth. We emphasize that these algorithms cannot be developed in isolation from applications, as many of the relevant issues do not arise at small scale or in simple model problems devoid of complex physics and/or geometry. Thus, to address algorithmic issues at the forefront of science-based simulation we require a code that is capable of solving problems _at_scale_ and that is sufficiently flexible to allow adaptation to new physics. Project description: Nek5000 is a petascale fluid/thermal simulation code used for a host of applications including reactor thermal hydraulics, combustion, MHD, oceanography, spatiotemporal chaos, and vascular flow modeling. Nek5000 is a grid-based PDE (partial differential equation) solver in three space dimensions and time. We have access to resources on BG/Q through INCITE and discretionary allocations. This request is to address mid-range capabilities. Our goal is to use LCRC machines to test the performance of mid-size problems (with 10,000 to 100000) elements with various compilers and compiler options. We also intend to use the time for problems in nuclear engineering such as boiling heat transfer (multiphase flows), thermal stripping and conjugate heat-transfer. This year we plan to continue to test various large-element cases which have been run with LES models using 3 different uRANS models that have been implemented in Nek5000. These runs typically need about 100-150K core-hours per case. We aim to study 4-6 such cases with the allocation this year. Additionally, we also intend to study some oscillatory problems that require simulations for long time-transients, that typically need about 10K core-hours per case. We intend to run about 20-30 of these cases. Industry partnership: None Project URL: http://www.mcs.anl.gov/~fischer/sem1b Current FY Hours Used: undetermined amount New FY Requested allocation: 600000 Q1: 150000 Q2: 150000 Q3: 150000 Q4: 150000 Justification: Near linear strong scaling has been seen in all problems studied. Typically, 3000 grid points/core is required to ensure both strong and weak scaling. Storage requirements: Thank You, The LCRC Accounts System