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Title:
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Authors:
Hubert Klahr, MPIA
Anders Johansen, MPIA
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Abstract:
It is of great importance to understand the transport and mixing properties of turbulence in protoplanetary Accretion Disks. Turbulent diffusion directly influences the chemical evolution in the disk and has an impact on the growth of dust particles to planetesimals. As a result the distribution of dust grains and molecules determines the observational features of the disk.
The first order approach is usually to assume the diffusion parameter to be exactly equal to the turbulent viscosity. We want to demonstrate in how far this assumption is justified. Therefore, we study the transport of small grains in a direct numerical simulation of turbulence in a protoplanetary accretion disk driven by the magneto rotational instability. We adopt the Pencil code in a shearing sheet approximation to measure the diffusion properties of the disk turbulence in relation to the measured Reynolds and Maxwell Stresses (e.g. ALPHA values). We find the diffusion to be anisotropic and show how it relates to the measured stresses.
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