Dr. Christian Schwarz
Publikationen
Ch. Schwarz, Ch. Beetz, J. Dreher, and R. GrauerLyapunov exponents and information dimension of the mass distribution in turbulent compressible flowsTurbulent density fluctuations in isothermal highly compressible turbulent flows are highly clumped and can be quantified by the scaling properties of powers of the mass distribution. This Eulerian quantity can be related to Lagrangian properties of the system given by the Lyapunov exponents of tracer particles advected with the flow. Using highly resolved numerical simulations, we show that the Kaplan-Yorke conjecture holds within numerical uncertainties. Physics Lett. A 374 (2010) 1039  
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L. Arnold, C. Beetz, J. Dreher, H. Homann, C. Schwarz and R. GrauerMassively Parallel Simulations of Solar Flares and Plasma TurbulenceSome of the outstanding problems in space- and astrophysical plasmasystems include solar flares and hydro- or magnetohydrodynamic turbulence (e.g. in the interstellar medium). Both fields demand for high resolution and thus numerical simulations need an efficient parallel implementation. We will describe the physics behind these problems and present the numerical frameworks for solving these problems on massive parallel computers. Parallel Computing: Architectures, Algorithms and Applications 15 (2008) 467
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C. Beetz, C. Schwarz, J. Dreher, R. GrauerDensity-PDFs and Lagrangian Statistics of highly compressible TurbulenceIn isothermal, highly compressible turbulent flows, density fluctuations follow a log-normal distribution. We establish a connection between these density fluctuations and the probability-density-functions (PDF) of Lagrangian tracer particles advected with the flow. Our predicted particle statistics is tested against large scale numerical simulations, which were performed with $512^3$ collocation points and 2 million tracer particles integrated over several dynamical times. Physics Letters A 372 (2008) 3037
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