Alvarez Fellow Aleksandar Donev was an invited participant and speaker at a focused workshop on "Numerical Analysis of Multiscale Computations" held at the Banff International Research Station (www.birs.ca) in Banff, Canada, from Dec. 6-11, 2009. He presented his work on "Hybrid methods for hydrodynamics of complex fluids" (with John Bell, Alejandro Garcia, and Berni Alder).

George Pau presented a poster titled "High Resolution Simulation and Characterization of Density-Driven Flow in CO2 Storage in Saline Aquifers" at the American Geophysical Union Fall Meeting, San Francisco, 14-18 December 2009. This work is done in collaboration with John Bell, Ann Almgren, Mike Lijewski, Karsten Pruess and Keni Zhang. Pruess and Zhang are scientists in the Environmental Science department at LBNL.

This year at Supercompuing 2009 (SC09), Berkeley Lab is incorporating an innovative display technology to show three-dimensional science and engineering data in 3D -- without the use of special glasses or viewers. The centerpiece of the display is a 24-inch Magic Planet globe made by Global Imagination.

Two of the data sets shown on the globe are results of simulations run using MAESTRO, CCSE's low Mach number astrophysics code, and CASTRO, CCSE's compressible astrophysics code. The MAESTRO runs were performed by by Mike Zingale of Stony Brook University, and the CASTRO runs were performed by Jason Nordhaus of Princeton University.

Bell's first invited lecture, on his work with Prof. Alej Garcia of San Jose State University and Alvarez Fellow Aleksandar Donev, will be at the meeting on "Multiscale Problems in Fluid Mechanics and Meteorology (MetStroem)" at the Freie Universitat in Berlin. His next talk, on his porous media work with Alvarez Fellow George Pau, will be given at the International Workshop on "Coupled Models in Energy, Hydrological and Climate Research" at the Weierstrass Institute for Applied Analysis and Stochastics.

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"Bell and his team, which includes LBNL scientists Marcus Day, Mike Lijewski and Vince Beckner, have simulated a low-swirl burner fueled by methane and hydrogen. Their model used the novel techniques of low Mach number with adaptive mesh refinement, which dynamically focuses computational effort where it is needed during a simulation."

"Even with these techniques, the simulations required 3 million processor hours on high-performance computers at the National Energy Research Scientific Computing Center (NERSC) at LBNL; the simulations would have been impossible without these methods."

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The first applications of CCSE's new compressible astrophysics code, CASTRO, to Type II core collapse supernovae were presented at the Conference on Stellar Death and Supernovae, held August 17-21, 2009, at the Kavli Institute for Theoretical Physics (KITP) at the University of California, Santa Barbara. Simulations using CASTRO were highlighted in an invited talk given by Adam Burrows from Princeton University and in a poster presented by Jason Nordhaus. The results focused on new 3D adaptive simulations of the collapse of the cores of massive stars, one that was induced to explode by neutrino heating and one that was allowed to fizzle. These simulations were performed on Franklin, the Cray XT4 supercomputer at NERSC.

According to Burrows, "Both were characterized by hydrodynamic instabilities whose nature was novel and complex. Though preliminary, these simulations suggest that the traditional view of a supernova exploded by neutrino heating may be viable, but perhaps only if carried out in three spatial dimensions at high resolution with careful attention to the neutrino transport."

CCSE postdocs Andy Nonaka and George Pau organized and chaired a two-part mini-symposium on "Adaptive mesh refinement strategies for simulating large multiphysics multiscale problems" for the IMACS World Congress on Computational and Applied Mathematics and Applications in Science and Engineering held in August, 2009. The conference, sponsored by the International Association for Mathematics and Computers in Simulation (IMACS), was held at the University of Georgia in Athens, Ga. Nonaka spoke in the August 4 session. Pau, who is a Luis W. Alvarez Postdoctoral Fellow, also gave a talk describing his work on simulation of nano-devices.

Seaborg Fellow Andy Aspden presented at the 22nd International Colloquium on the Dynamics of Explosions and Reacting Systems in Minsk, Belarus, held in July 2009. His talk was titled "Turbulent-Flame Interactions in Lean Premixed Hydrogen", and discussed the transition to the distributed burning regime. Further details of this work can be found here.