Title: Residual Distribution Schemes for Astrophysical Flows

Speaker: Prof. James Rossmanith, University of Wisconsin

Date/Time: Wednesday, August 29, 2007, 9:00am - 10:00 am

Location: Building 823/Breezeway (Sandia NM)

Brief Abstract: An important problem in modern astrophysics is to understand the accretion of ionized gases onto a black hole and the formation of relativistic jets that can sometimes result from this process. Even with significant simplifying assumptions, including that the spacetime is static and that the accreting dust obeys relativistic fluid equations, accurate numerical computations of such flows are still quite challenging to obtain. Some of the difficulties include the strong curvature of spacetime near the event horizon, the divergence-free condition on the magnetic field, the complex equation structure due to the Lorentz factor, and non-trivial balances between flux gradients and geometric source terms. In this talk we will describe an effort to develop genuinely multidimensional, high-resolution, shock-capturing schemes on unstructured grids for solving the relativistic Euler and MHD equations. The resulting method will be applied to several axisymmetric computations of black hole accretion.