Petascale Computational Fluid Dynamics

Rensselaer Polytechnic Institute, Troy NY

Investigators

Abstract

This proposed research will develop an adaptive computational fluid dynamics solver that will achieve sustained petaflop performance. A mature finite element method will be paired with anisotropic adaptive meshing procedures to provide a powerful tool for attacking fluid flow problems where boundary and shear layers develop highly anisotropic solutions that can only be located and resolved through adaptivity. These flow problems can involve complicated geometries and complex physics such as fluid turbulence and multiphase interactions, resulting in discretizations so large that only petascale simulation offers the resources required for a complete solution. Two applications will be used to develop the computational methodology. These are simulation of trailing edge noise (compressible-explicit), ii) two-phase annular flow, and iii) cardiovascular simulation (both incompressible implicit); each yielding fundamental scientific insight into currently, poorly understood flow physics. Intellectual Merit. Algorithms to extend an adaptive CFD solver to petaflop performance will be developed to maintain scaling in the response to emerging architectures (multicore, CELL, clockrate, bus, cache) and networks (bandwidth, latency, communication layout/mapping, asynchronous communication). This solver and others will be enabled by developments in parallel, anisotropic adaptive meshing that affords a dramatic reduction in the elements required to accurately represent anisotropic physics. Both developments will be guided by a petascale emulator that does not perturb the heap or stack memory, fits within an MPI layer and predicts performance accurately in the presence of system faults. The proposed applications will lead to a better understanding of the complex physics of turbulent flow, noise produced by turbulent flows, multiphase flows and the interaction of mechanics and biology in the human cardiovascular system. This fundamental scientific insight will be gained from high fidelity simulations that will be the first of their kind, and will be made possible by petascale resources and algorithms. Broader Impacts. A petascale adaptive CFD solver will demonstrate that robust, open source software, applicable to a very broad range of flow physics, can sustain petaflop performance, providing a path for all continuum-based PDE solvers to follow, greatly extending our nations modeling and simulation capacity. Additionally, the petascale emulator will be extended to other classes of parallel codes. There will be an abundance of opportunities for students from diverse sub-fields to work together on the challenges proposed. The proposed petascale applications will impact critical areas of national need including energy, environment and improved patient care.