1994/02/21 by Matthias Steinmetz, Steinmetz, Matthias
Engineering · Physics and Astronomy · #Astrophysics (astro-ph) #FOS: Physical sciences #Fluid Dynamics Simulations and Interactions #Fluid Dynamics and Heat Transfer #Spacecraft and Cryogenic Technologies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9402050
7 pages, compressed uu-encoded postscript file (116kB), contribution to the exhibition on High Performance Computing and Networking (HPCN94), Munich, April 18-20, 1994
arxiv created 1994/02/21 · openalex publication_date 1994/02/21 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present numerical simulations of galaxy formation, one of the most\nchallenging problems in computational astrophysics. The key point in such\nsimulations is the efficient solution of the N--body problem. If the gas of a\ngalaxy is treated by means of smoothed particle hydrodynamics (SPH), the\nhydrodynamic equations can be reduced to a form similar to that of the N--body\nproblem. A straightforward implementation requires a computational effort\n\∝ N2, making it prohibitively expensive to simulate systems larger\nthan 105 particles even on the largest available supercomputers. After a\ndescription of the physical and numerical problems, we shortly review the\nstandard numerical methods to tackle these problems and discuss their\nadvantages and drawbacks. We also present a completely different approach to\nperform such simulations using a workstation in combination with the special\npurpose hardware sc Grape. After a discussion of the main features of sc\nGrape, we present a simple implementation of a sc SPH--N--body code on such\na configuration. Comparing results and performance of these two approaches, we\nshow, that with an investment of US \$ 50000, the problem can be solved up to 5\ntimes faster than on a sc Cray YMP.\n