Hello, A yearly allocation for the LCRC cluster has been requested with the following updated information: Submitter/PI: Ray Bair Project Name: NuclearBurn Division: CLS Project title: Buoyancy-Driven Turbulent Nuclear Burning Associated funding: Astrophysics and Cosmology Strategic Initiative LDRD Other Systems: Intrepid Science: Type Ia supernovae are powerful stellar explosions with the property that a large majority of explosions of this type are remarkably homogeneous; yet the mechanism by which they explode is not well understood. A proposed mechanism is the Gravitationally Confined Detonation (GCD) model, where ash created during a deflagration (subsonic nuclear combustion) is ejected from the star, flows around the surface, and collides with itself at the opposite point of breakout, sparking a detonation. In this joint Argonne - U. Chicago LDRD project we will quantify the scale-dependence of flame surface structure induced by buoyancy-generated turbulence. The current work focuses on determining the sensitivity of the properties of SN Ia explosions to the initial conditions. These simulations also provide input data to radiation transfer calculations of the light curves and spectra of SN Ia, enabling the Flash Center to validate the four current models of SNe Ia by comparing them with high-quality observations. Project description: This project carries out high-resolution 2D studies of the how buoyancy instabilities enhance flame surface and burning rate for thermonuclear flames. These studies compliment the 3D studies being performed elsewhere. The Center for Astrophysical Thermonuclear Flashes (the "Flash Center") has developed FLASH, a highly capable, fully modular, extensible, community code that is widely used in astrophysics, cosmology, fluid dynamics, plasma physics, and other fields. FLASH has demonstrated good scaling on the largest systems. For the larger 3D simulations in this LDRD project, the FLASH computations scale to the entire Intrepid system. For the 2D simulations and test 3D problems we plan on Fusion, We used about 90K hours in 6 months of FY2010, and projecting to FY2011 our runs should take about 300K hours. Project URL: Current FY Hours Used: undetermined amount New FY Requested allocation: 300000 Justification: For example, in strong scaling runs, the execution time of FLASH benchmark runs varies less than 7% from 128 to 16384 processors. Thank You, The LCRC Accounts System